TY - JOUR
A1 - Linberg, Kevin
A1 - Ali, Naveed Zafar
A1 - Etter, M.
A1 - Michalchuk, Adam
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - A Comparative Study of the Ionic Cocrystals NaX (α-d-Glucose)2 (X = Cl, Br, I)
JF - Crystal growth & design
N2 - The mechanochemical formation of the ionic cocrystals of glucose (Glc) and sodium salts Glc2NaCl·H2O (1) and Glc2NaX (X = Br (2), I (3)) is presented. Products are formed by co-milling Glc with three sodium salts (NaCl, NaBr, NaI). The ionic cocrystals were obtained under both neat grinding and liquid-assisted grinding conditions, the later found to accelerate the reaction kinetics. The crystal structures of the ionic cocrystals (2) and (3) were solved from powder X-ray diffraction data. The structure solution contrasts with the structure of Glc2NaCl·H2O (1) where the electron density at three halide crystallographic sites is modeled as of being the intermediate between water molecule and a chloride ion. The reaction pathways of the three ionic cocrystals were investigated in real time using our tandem approach comprising a combination of in situ synchrotron powder X-ray diffraction and Raman spectroscopy. The results indicate the rapid formation of each cocrystal directly from their respective starting materials without any intermediate moiety formation. The products were further characterized by DTA-TG and elemental analysis.
KW - In situ
KW - Co-crystal
KW - Mechanochemistry
KW - Glucose
PY - 2019
DO - https://doi.org/10.1021/acs.cgd.8b01929
VL - 19
IS - 8
SP - 4293
EP - 4299
PB - ACS Publications
AN - OPUS4-48781
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mazzeo, P
A1 - Lampronti, G
A1 - Michalchuk, Adam
A1 - Belenguer, A
A1 - Bacchi, A
A1 - Emmerling, Franziska
T1 - Accurate extrinsic and intrinsic peak broadening modelling for time-resolved in situ ball milling reactions via synchrotron powder X-ray diffraction
JF - Faraday Discussions
N2 - The debate on the mechanisms which underpin mechanochemical reactions via ball mill grinding is still open. Our ability to accurately measure the microstructural (crystal size and microstrain) evolution of materials under milling conditions as well as their phase composition as a function of time is key to the in-depth understanding of the kinetics and driving forces of mechanochemical transformations. Furthermore, all ball milling reactions end with a steady state or milling equilibrium – represented by a specific phase composition and relative microstructure – that does not change as long as the milling conditions are maintained. The use of a standard sample is essential to determine the instrumental contribution to the X-ray powder diffraction (XRPD) peak broadening for time-resolved in situ (TRIS) monitoring of mechanochemical reactions under in operando conditions. Using TRIS-XRPD on a ball milling setup, coupled with low-energy synchrotron radiation, we investigated different data acquisition and analysis strategies on a silicon standard powder. The diffraction geometry and the microstructural evolution of the standard itself have been studied to model the instrumental contribution to XRPD peak broadening throughout the grinding activity. Previously proposed functions are here challenged and further developed. Importantly, we show that minor drifts of the jar position do not affect the instrumental resolution function significantly. We here report and discuss the results of such investigations and their application to TRIS-XRPD datasets of inorganic and organic ball mill grinding reactions.
KW - Mechanochemistry
KW - In situ diffraction
KW - Synchrotron radiation
KW - Sustainable chemisry
PY - 2022
DO - https://doi.org/10.1039/d2fd00104g
SP - 1
EP - 17
PB - Royal Society of Chemistry
AN - OPUS4-55932
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tumanov, I.
A1 - Tumanov, E.
A1 - Michalchuk, Adam
T1 - Ball size or ball mass – what matters in organic mechanochemical synthesis?
JF - CrystEngComm
N2 - Ball mass is an important parameter that is known to have an influence on the outcome of a mechanochemical reaction induced by ball-milling. A standard way of modifying the ball mass is to change the size of the ball made of the same material. In this case, however, a change in mass is accompanied by a simulatneous change in the ball size. It is therefore not possible to disentangle the effects of mass and Surface area in these cases. In the present work we report the results of experiments with specially designed and manufactured balls in which (1) milling ball mass is held constant, but their size differs, and (2) the ball mass is altered, with the diameter of the milling ball being held constant. Using the cocrystallisation of theophylline + nicotinamide as a case study it was found that both diameter and ball mass play crucial roles in determining the rate of a mechanochemical reaction. For comparison, we have also used milling balls with the same size (different mass), and others with the same mass (different size) made of different materials, as would be “traditional”. It was found that, despite having the same size, the lightest milling ball (nylon) was the most efficient in initiating the co-crystallisation, presumably due to the sorption of EtOH. Hence, the results of this manuscript also demonstrate how milling ball material can in fact be the most influential parameter, and potentially counterintuitive to classical mechanics.
KW - Mechanochemistry
KW - XRD
PY - 2019
DO - https://doi.org/0.1039/c8ce02109k
VL - 21
SP - 2174
EP - 2179
PB - RSC Royal Society of Chemistry
AN - OPUS4-47851
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Al-Terkawi, Abdal-Azim
A1 - Scholz, G.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Reinsch, Stefan
A1 - Kemnitz, E.
A1 - Emmerling, Franziska
T1 - Ca- and Sr- tetrafluoroisophthalates: mechanochemical synthesis, characterization, and ab initio structure determination
JF - DALTON TRANSACTIONS
N2 - New fluorinated coordination polymers were prepared mechanochemically by milling the alkaline earth metal hydroxides MII(OH)2·xH2O (MII: Ca, Sr) with tetrafluoroisophthalic acid (H2mBDC-F4). The structures of [{Ca(mBDC-F4)(H2O)2}·H2O] and [{Sr(mBDC-F4)(H2O)2}·H2O] were determined based on ab initio calculations and their powder X-ray diffraction (PXRD) data. The compounds are isomorphous and crystallize in the orthorhombic space group P212121. The determined structures were validated by using extended X-ray absorption (EXAFS) data. The new materials were thoroughly characterized using elemental analysis, thermal analysis, magic angle spinning NMR, and attenuated total reflection-infrared spectroscopy. Further characterization methods such as BET, dynamic vapor sorption, and scanning electron microscopy imaging were also used. Our investigations indicate that mechanochemistry is an efficient method for preparing such materials.
KW - Mechanochemistry
KW - In situ
KW - XRD
KW - Coordination polymers
PY - 2017
UR - http://pubs.rsc.org/-/content/articlehtml/2017/dt/c7dt00734e
DO - https://doi.org/10.1039/c7dt00734e
VL - 46
IS - 18
SP - 6003
EP - 6012
AN - OPUS4-41516
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Al-Terkawi, Abdal-Azim
A1 - Prinz, Carsten
A1 - Scholz, Gudrun
A1 - Kemnitz, Erhard
A1 - Emmerling, Franziska
T1 - Ca-, Sr-, and Ba-Coordination polymers based on anthranilic acid via mechanochemistry
JF - Daltron Transaction
N2 - Ca-, Sr-, and Ba-Based coordination polymers (CPs) were prepared mechanochemically by milling metal-hydroxide samples with anthranilic acid (oABAH). {[Ca(oABA)2(H2O)3]}n consists of one-dimensional polymeric chains that are further connected by a hydrogen-bonding network. {[Sr(oABA)2(H2O)2]·H2O}n is a one-dimensional CP in which water molecules bridge Sr2+ ions and increase the dimensionality by building an extended network. {[Ba(oABA)2(H2O)]}n crystallizes as a two-dimensional CP comprising one bridging water molecule. The cation radii influence the inorganic connectivity and dimensionality of the resulting crystal structures. The crystal structures were refined from powder X-ray diffraction data using the Rietveld method. The local coordination environments were studied via extended X-ray absorption fine structure (EXAFS) measurements. The compounds were further characterized using comprehensive analytical methods such as elemental analysis, thermal analysis, MAS NMR, imaging, and dynamic vapor sorption (DVS) measurements. Compounds 1, 2, and 3 exhibit small surface areas which decrease further after thermal annealing experiments. All compounds exhibit a phase transformation upon heating, which is only reversible in 3.
KW - Mechanochemistry
KW - XRD
PY - 2019
DO - https://doi.org/10.1039/c9dt00991d
SN - 1477-9226
SN - 1477-9234
VL - 48
IS - 19
SP - 6513
EP - 6521
PB - Royal Society of Chemistry
AN - OPUS4-48014
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wilke, Manuel
A1 - Batzdorf, Lisa
A1 - Fischer, Franziska
A1 - Rademann, Klaus
A1 - Emmerling, Franziska
T1 - Cadmium phenylphosphonates: preparation, characterisation and in situ investigation
JF - RSC Advances
N2 - The successful mechanochemical syntheses of three cadmium phenylphosphonates indicates that mechanochemistry is ideally suited for synthesizing metal phosphonates. With this powerful synthesis tool it is possible to synthesize rapidly and efficiently both known and novel phosphonates. The Crystal structures of the two new compounds, and, were solved from PXRD data. They contain monodeprotonated phenylphosphonate and neutral phenylphosphonic acid ligands. The synthesis pathways of all three compounds were investigated in situ. A diffusion mechanism is corroborated by our findings.
Intermediates could be detected and identified. The kinetically favored product (3) could always be detected during the syntheses. The thermodynamic stability of the compounds and the stoichiometric ratio of the starting materials are the two directing factors for the synthesis of the final products.
KW - Mechanochemistry
KW - Metal phosphonate
KW - In situ
KW - MOF
KW - XRD
PY - 2016
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-363322
DO - https://doi.org/10.1039/c6ra01080f
SN - 2046-2069
VL - 6
IS - 42
SP - 36011
EP - 36019
PB - Royal Soc Chemistry
CY - Cambridge, UK
AN - OPUS4-36332
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Emmerling, Franziska
A1 - Martins, Ines
T1 - Carbamazepine Dihydroxybenzoic Acid Cocrystals: Exploring Packing Interactions and Reaction Kinetics
JF - Crystal Growth and Design
N2 - Herein, we present the mechanochemical formation of three new cocrystals containing the active pharmaceutical ingredient carbamazepine and dihydroxybenzoic acids as coformers (CBZ:2,4-DHBA 1:1, CBZ:2,5-DHBA 1:1, and CBZ:2,6-DHBA 1:1). Rietveld methods were used for three different purposes: (i) refining all structures solved using powder X-ray diffraction, (ii) performing a quantitative phase analysis of the diffraction data collected from ex situ mechanochemical reactions at different milling times, and (iii) determining the cocrystallization kinetic profiles. The rate of cocrystallization was found to be higher for the formation of CBZ:2,4-DHBA and CBZ:2,6-DHBA, reaching an equilibrium after 600 s of milling. In the case of CBZ:2,5-DHBA a short induction period of 20 s was detected prior to the start of the reaction and an equilibrium was reached after 1200 s. An empirical trend between the rate of cocrystallization and the structural complexity of the cocrystal product was found. The slowest cocrystallization rate observed for CBZ:2,5-DHBA corresponds to the crystal structure deviating substantially from the hydrogen-bonding motif found in the reactants.
KW - Mechanochemistry
KW - In situ real-time monitoring
KW - Kinetics
PY - 2021
DO - https://doi.org/10.1021/acs.cgd.1c00902
VL - 21
IS - 12
SP - 6961
EP - 6970
PB - ACS Publications
AN - OPUS4-54407
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Oliveira, P. F. M.
A1 - Torresi, R.
A1 - Emmerling, Franziska
A1 - Carmago, P.
T1 - Challenges and opportunities in the bottom-up mechanochemical synthesis of noble metal nanoparticles
JF - Journal of Materials Chemistry A
N2 - Mechanochemistry is a promising alternative to solution-based protocols across the chemical sciences, enabling different types of chemistries in solvent-free and environmentally benign conditions. The use of mechanical energy to promote physical and chemical transformations has reached a high level of refinement, allowing for the design of sophisticated molecules and nanostructured materials. Among them, the synthesis of noble metal nanoparticles deserves special attention due to their catalytic applications. In this review, we discuss the recent progress on the development of mechanochemical strategies for the controlled synthesis of noble metal nanostructures. We start by covering the fundamentals of different preparation routes, namely top-down and bottom-up approaches. Next, we focus on the key examples of the mechanochemical synthesis of non-supported and supported metal nanoparticles as well as hybrid nanomaterials containing noble metals. In these examples, in addition to the principles and synthesis mechanisms, their performances in catalysis are discussed. Finally, a perspective of the field is given, where we discuss the opportunities for future work and the challenges of mechanochemical synthesis to produce well-defined noble metal nanoparticles.
KW - Mechanochemistry
KW - Nanoparticles
PY - 2020
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-512080
DO - https://doi.org/10.1039/D0TA05183G
VL - 8
IS - 32
SP - 16114
AN - OPUS4-51208
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Lampronti, G.
A1 - Michalchuk, Adam
A1 - Mazzeo, P.
A1 - Belenguer, Ana
A1 - Sanders, J. K. M.
A1 - Bacchi, A.
A1 - Emmerling, Franziska
T1 - Changing the game of time resolved X-ray diffraction on the mechanochemistry playground by downsizing
JF - Nature Communications
N2 - Time resolved in situ (TRIS) monitoring has revolutionised the study of mechanochemical transformations but has been limited by available data quality. Here we report how a combination of miniaturised grinding jars together with innovations in X-ray powder diffraction data collection and state-of-the-art analysis strategies transform the power of TRIS synchrotron mechanochemical experiments. Accurate phase compositions, comparable to those obtained by ex situ measurements, can be obtained with small sample loadings. Moreover, microstructural parameters (crystal size and microstrain) can be also determined with high confidence. This strategy applies to all chemistries, is readily implemented, and yields high-quality diffraction data even using a low energy synchrotron source. This offers a direct avenue towards the mechanochemical investigation of reactions comprising scarce, expensive, or toxic compounds. Our strategy is applied to model systems, including inorganic, metal-organic, and organic mechanosyntheses, resolves previously misinterpreted mechanisms in mechanochemical syntheses, and promises broad, new directions for mechanochemical research.
KW - Mechanochemistry
KW - Synchrotron radiation
KW - Material synthesis
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-535932
DO - https://doi.org/10.1038/s41467-021-26264-1
SN - 2041-1723
VL - 12
IS - 1
SP - 1
EP - 9
PB - Nature Publishing Group
CY - London
AN - OPUS4-53593
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Surov, A.
A1 - Vasilev, N.
A1 - Voronin, A.
A1 - Churakov, A.
A1 - Emmerling, Franziska
A1 - Perlovich, G.
T1 - Ciprofloxacin salts with benzoic acid derivatives: structural aspects, solid-state properties and solubility performance
JF - Crystengcomm
N2 - n this work, three new pharmaceutical hydrated salts of ciprofloxacin with selected derivatives of benzoic acid, namely 4-hydroxybenzoic acid, 4-aminobenzoic acid and gallic acid, were obtained and systematically investigated by several solid-state analytical techniques. In situ Raman spectroscopy was applied to elucidate the alternative pathways of the solid forms' formation under mechanochemical conditions. Crystal structure analysis and a CSD survey allowed us to establish a distinct supramolecular motif formed by infinite columnar stacks of ciprofloxacin dimers arranged in the “head-to-tail” manner. An alternative “head-to-head” packing arrangement was only observed in the crystal of the hydrated ciprofloxacin salt with 4-aminobenzoic acid. In addition, the pH-solubility behavior of the solid forms was thoroughly investigated. Furthermore, a distinct structure–property relationship between the specific features of the supramolecular organization of the hydrated salts and their solubility was observed and discussed.
KW - Mechanochemistry
KW - XRD
PY - 2020
DO - https://doi.org/10.1039/D0CE00514B
VL - 22
IS - 25
SP - 4238
EP - 4249
AN - OPUS4-51818
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Linberg, Kevin
A1 - Röder, Bettina
A1 - Al-Sabbagh, Dominik
A1 - Emmerling, Franziska
A1 - Michalchuk, Adam
T1 - Controlling polymorphism in molecular cocrystals by variable temperature ball milling
JF - Faraday Discussions
N2 - Mechanochemistry offers a unique opportunity to modify and manipulate crystal forms, often providing new products as compared with conventional solution methods. While promising, there is little known about how to control the solid form through mechanochemical means, demanding dedicated investigations. Using a model organic cocrystal system (isonicotinamide:glutaric acid), we here demonstrate that with mechanochemistry, polymorphism can be induced in molecular solids under conditions seemingly different to their conventional thermodynamic (thermal) transition point. Whereas Form II converts to Form I upon heating to 363 K, the same transition can be initiated under ball milling conditions at markedly lower temperatures (348 K). Our results indicate that mechanochemical techniques can help to reduce the energy barriers to solid form transitions, offering new insights into controlling polymorphic forms. Moreover, our results suggest that the nature of mechanochemical transformations could make it difficult to interpret mechanochemical solid form landscapes using conventional equilibrium-based tools.
KW - Mechanochemistry
KW - Polymorphism
KW - TRIS
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-564728
DO - https://doi.org/10.1039/d2fd00115b
SP - 1
EP - 16
PB - Royal Society of Chemistry
AN - OPUS4-56472
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Linberg, Kevin
A1 - Röder, Bettina
A1 - Al-Sabbagh, Dominik
A1 - Emmerling, Franziska
A1 - Michalchuk, Adam
T1 - Controlling polymorphism in molecular cocrystals by variable temperature ball milling
JF - Faraday Discussions
N2 - Mechanochemistry offers a unique opportunity to modify and manipulate crystal forms, often providing new products as compared with conventional solution methods. While promising, there is little known about how to control the solid form through mechanochemical means, demanding dedicated investigations. Using a model organic cocrystal system (isonicotinamide:glutaric acid), we here demonstrate that with mechanochemistry, polymorphism can be induced in molecular solids under conditions seemingly different to their conventional thermodynamic (thermal) transition point.
Whereas Form II converts to Form I upon heating to 363 K, the same transition can be initiated under ball milling conditions at markedly lower temperatures (348 K). Our results indicate that mechanochemical techniques can help to reduce the energy barriers to solid form transitions, offering new insights into controlling polymorphic forms. Moreover, our results suggest that the nature of mechanochemical transformations could make it difficult to interpret mechanochemical solid form landscapes using conventional equilibrium-based tools.
KW - Mechanochemistry
KW - Kinetics
KW - In situ
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-558878
DO - https://doi.org/10.1039/d2fd00115b
SP - 1
EP - 16
PB - Royal Society of Chemistry
AN - OPUS4-55887
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wilke, Manuel
A1 - Kabelitz, Anke
A1 - Zimathies, Annett
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Crystal structure and in situ investigation of a mechanochemical synthesized 3D zinc N-(phosphonomethyl)glycinate
JF - Journal of Materials Science
N2 - The mechanochemical synthesis of the zinc N-(phosphonomethyl)glycinate Zn(O₃PCH₂NH₂CH₂CO₂) H₂O is presented. The structure was solved from powder X-ray diffraction (PXRD) data. In the three-dimensional pillared structure, the Zn atoms are coordinated tetrahedrally. In situ investigations of the reaction process with synchrotron PXRD and Raman spectroscopy reveal a two-step process including the formation of an intermediate.
KW - Mechanochemistry
KW - Metal phosphonate
KW - In situ
PY - 2017
DO - https://doi.org/10.1007/s10853-017-1121-7
SN - 0022-2461
SN - 1573-4803
VL - 52
IS - 20
SP - 12013
EP - 12020
PB - Springer
CY - New York
AN - OPUS4-41490
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Matoga, D.
A1 - Roztocki, K.
A1 - Wilke, Manuel
A1 - Emmerling, Franziska
A1 - Oszajca, M.
A1 - Fitta, M.
A1 - Bałanda, M.
T1 - Crystalline bilayers unzipped and rezipped: solid-state reaction cycle of a metal–organic framework with triple rearrangement of intralayer bonds
JF - CrystEngComm
N2 - We present a series of remarkable structural transformations for a family of layered metal–organic frameworks (MOFs) in a three-step solid-state reaction cycle. The cycle represents new dynamic behavior of 2D coordination polymers and involves the sequence of reactions: {[Mn2(ina)4(H2O)2]·2EtOH}n (JUK-1) → {(NH4)2[Mn(ina)2(NCS)2]}n·xH2O (JUK-2) → {[Mn2(ina)2(Hina)2(NCS)2]}n (JUK-3) → JUK-1 (Hina = isonicotinic acid), each accompanied by rearrangement of intralayer coordination bonds and each induced by a different external stimulus. In situ investigation of the first step of the cycle by combined synchrotron X-ray diffraction and Raman spectroscopy reveals direct mechanochemical unzipping of JUK-1 bilayers to respective JUK-2 layers with reaction rates dependent on the milling conditions. In contrast, the reverse zipping of JUK-2 layers involves two steps and proceeds through a new MOF (JUK-3) whose structure was elucidated by powder X-ray diffraction. Magnetic measurements confirm conversions of manganese nodes in the reaction cycle. The findings indicate the possibility of developing coordination-based assemblies with large structural responses for use in smart stimuli-responsive systems and sensor technologies.
KW - Mechanochemistry
KW - In situ
KW - XRD
KW - MOF
PY - 2017
UR - http://pubs.rsc.org/is/content/articlehtml/2017/ce/c7ce00655a
DO - https://doi.org/10.1039/C7CE00655A
VL - 19
SP - 2987
EP - 2995
AN - OPUS4-41517
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Cakir, Cafer Tufan
A1 - Radtke, Martin
A1 - Haider, M. Bilal
A1 - Emmerling, Franziska
A1 - F. M. Oliveira, P.
A1 - Michalchuk, Adam A. L.
T1 - Dispersive x-ray absorption spectroscopy for time-resolved in situ monitoring of mechanochemical reactions
JF - Journal of chemical physics
N2 - X-ray absorption spectroscopy (XAS) provides a unique, atom-specific tool to probe the electronic structure of solids. By surmounting long-held limitations of powder-based XAS using a dynamically averaged powder in a Resonant Acoustic Mixer (RAM), we demonstrate how time-resolved in situ (TRIS) XAS provides unprecedented detail of mechanochemical synthesis. The use of a custom-designed dispersive XAS (DXAS) setup allows us to increase the time resolution over existing fluorescence measurements from ∼15 min to 2 s for a complete absorption spectrum. Hence, we here establish TRIS-XAS as a viable method for studying mechanochemical reactions and sampling reaction kinetics. The generality of our approach is demonstrated through RAM-induced (i) bottom-up Au nanoparticle mechanosynthesis and (ii) the synthesis of a prototypical metal organic framework, ZIF-8. Moreover, we demonstrate that our approach also works with the addition of a stainless steel milling ball, opening the door to using TRIS-DXAS for following conventional ball milling reactions. We expect that our TRIS-DXAS approach will become an essential part of the mechanochemical tool box.
KW - In situ studies
KW - Dipsersive XAS
KW - Mechanochemistry
KW - Time-resolved
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567659
DO - https://doi.org/10.1063/5.0130673
SN - 1089-7690
VL - 157
IS - 21
SP - 1
EP - 12
PB - American Institute of Physics
CY - Melville, NY
AN - OPUS4-56765
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wilke, Manuel
A1 - Bach, S.
A1 - Gorelik, T.
A1 - Kolb, U.
A1 - Tremel, W.
A1 - Emmerling, Franziska
T1 - Divalent metal phosphonates – new aspects for syntheses, in situ characterization and structure solution
JF - Zeitschrift für Kristallographie - Crystalline Materials
N2 - Divalent metal phosphonates are promising hybrid materials with a broad field of application. The rich coordination chemistry of the phosphonate linkers enables the formation of structures with different dimensionalities ranging from isolated complexes and layered structures to porous frameworks incorporating various functionalities through the choice of the building blocks.
In brief, metal phosphonates offer an interesting opportunity for the design of multifunctional materials. Here, we provide a short review on the class of divalent metal phosphonates discussing their syntheses, structures, and applications. We present the advantages of the recently introduced mechanochemical pathway for the Synthesis of divalent phosphonates as a possibility to generate new, in certain cases metastable compounds. The benefits of in situ investigation of synthesis mechanisms as well as the implementation of sophisticated methods for the structure analysis of the resulting compounds are discussed.
KW - Metal phosphonate
KW - Mechanochemistry
PY - 2017
DO - https://doi.org/10.1515/zkri-2016-1971
SN - 2194-4946
SN - 2196-7105
VL - 232
IS - 1-3
SP - 209
EP - 222
PB - De Gruyter
AN - OPUS4-40003
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Emmerling, Franziska
A1 - Tumanov, N.
A1 - Tumanova, N.
A1 - Fischer, Franziska
A1 - Morelle, F.
A1 - Ban, V.
A1 - Robeyns, K.
A1 - Filinchuk, Y.
A1 - Wouters, J.
A1 - Leyssens, T.
T1 - Exploring polymorphism and stoichiometric diversity in naproxen/proline cocrystals
JF - CrystEngComm
N2 - We present naproxen/proline cocrystals discovered when combining enantiopure and racemic naproxen and proline. Using liquid-assisted grinding as the main method to explore the variety of crystal forms in this system, we found 17 cocrystals, of which the structures of only four of them were previously known. The naproxen/proline system exhibited multiple polymorphs of 1 : 1 stoichiometry as well as more rare cocrystals with 1 : 2 and 2 : 3 stoichiometries, two cocrystal hydrates and one cocrystal solvate. In situ ballmilling, used to monitor liquid-assisted grinding reactions, revealed that the solvent dictates the reaction intermediates even if the final reaction product stays the same. Synchrotron X-ray diffraction data collected in situ upon heating allowed us to monitor directly the phase changes upon heating and gave access to pure diffraction patterns of several cocrystals, thus enabling their structure determination from powder X-ray diffraction data; this method also confirmed the formation of a conglomerate in the RS-naproxen/DL-proline system. Proline in cocrystals kept its ability to form charge-assisted head-to-tail
N-H⋯O hydrogen bonds, typical of pure crystalline amino acids, thus increasing the percentage of strong chargeassisted interactions in the structure and consequently providing some of the cocrystals with higher melting points as compared to pure naproxen. The majority of drugs are chiral, and hence, these data are of importance to the pharmaceutical industry as they provide insight into the challenges of chiral cocrystallization.
KW - In situ
KW - Mechanochemistry
KW - XRD
PY - 2018
UR - https://pubs.rsc.org/en/Content/ArticleLanding/CE/2018/C8CE01338A#!divAbstract
DO - https://doi.org/10.1039/c8ce01338a
SN - 1466-8033
VL - 20
IS - 45
SP - 7308
EP - 7321
PB - Royal Society of Chemistry
CY - London
AN - OPUS4-46913
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Casali, L.
A1 - Broll, V.
A1 - Ciurili, S.
A1 - Braga, D.
A1 - Emmerling, Franziska
A1 - Gepioni, F.
T1 - Facilitating Nitrification Inhibition through Green, Mechanochemical Synthesis of a Novel Nitrapyrin Complex
JF - Crystal Growth and Design
N2 - Nitrapyrin (NP) is applied to cultivated soils to inhibit the enzymatic activity of ammonia monooxygenase (AMO), but its poor aqueous solubility and high volatility severely limit its application. β-Cyclodextrin (β-CD) is commonly used to form inclusion complexes with hydrophobic molecules, improving water solubility and stability upon complexation. Here we report on the mechanochemical synthesis of the inclusion complex β-CD·NP, characterized via a combination of solid-state techniques, including exsitu and in situ X-ray diffraction, Raman and NMR spectroscopies, transmission electron microscopy, and energy dispersive X-ray spectroscopy. The pure inhibitor NP was also structurally characterized. The β-CD·NP complex presents improved solubility and thermal stability, and still inhibits the enzymatic activity of AMO with high efficacy. All results indicate that the inclusion of NP into β-CD represents a viable route for the preparation of a novel class of inhibitors, with improved properties related to stability, water solubility, and good inhibition activity.
KW - Mechanochemistry
KW - Nitrification
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537154
DO - https://doi.org/10.1021/acs.cgd.1c00681
VL - 21
IS - 10
SP - 5792
EP - 5799
PB - ACS Publications
AN - OPUS4-53715
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wilke, Manuel
A1 - Klimakow, Maria
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Fast and efficient synthesis of a host guest system: a mechanochemical approach
JF - CrystEngComm
N2 - An unusually fast and effective synthesis procedure for a host guest system consisting of a metal organic framework (MOF) and a polyoxometalate (POM) is described. The material was synthesised mechanochemically and the evolution of the structure was monitored ex and in situ using synchrotron X-ray diffraction (XRD).
KW - Mechanochemistry
KW - MOF
KW - in situ
PY - 2016
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-354910
UR - http://pubs.rsc.org/en/Content/ArticleLanding/2016/CE/C5CE01868D#!divAbstract
DO - https://doi.org/10.1039/C5CE01868D
VL - 18
IS - 7
SP - 1096
EP - 1100
AN - OPUS4-35491
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Bach, S.
A1 - Visnow, E.
A1 - Panthöfer, M.
A1 - Gorelik, T.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Gulo, A.
A1 - Kolb, U.
A1 - Emmerling, Franziska
A1 - Lind, C.
A1 - Tremel, W.
T1 - Hydrate networks under mechanical stress – A case study for Co3(PO4)2·8H2O
JF - European Journal of Inorganic Chemistry
N2 - The nature of the bound water in solids with hydrogen-bonded networks depends not only on temperature and pressure but also on the nature of the constituents. The collapse and reorientation of these network structures determines the stability of hydrated solids and transitions to other crystalline or amorphous phases. Here, we study the mechanochemically induced loss of bound water in Co₃(PO₄)₂·8H₂O and compare this process to the behavior under hydrostatic pressure.
The associated phase transition and its kinetics were monitored by X-ray powder diffraction with Synchrotron radiation and quantitative IR spectroscopy. High shearing forces are responsible for the degradation of the hydrogen-bonded network and the concomitant crystalline–amorphous transformation. UV/Vis spectroscopy, extended X-ray absorption spectroscopy (EXAFS), and X-ray absorption near-edge spectroscopy (XANES) provided information about the short-range order in the amorphous solid, and thermal analysis revealed its composition and showed that the moderate charge densities of the Co²⁺ and PO₄³⁻ ions, which make the hydration enthalpy comparable to the binding energy of the counteranions, and the Formation of hydrogen-bonded networks favor multistage crystallization processes associated with the release and uptake of coordinated water. The changes of the Co²⁺ coordination induce a color change from pink to blue; therefore, Co₃(PO₄)₂·8H₂O can be used as an overheat temperature indicator.
KW - Mechanochemistry
KW - Amorphous materials
KW - Hydrates
KW - Cobalt
KW - Phosphates
PY - 2016
DO - https://doi.org/10.1002/ejic.201501481
SN - 1434-1948
SN - 1099-0682
VL - 2016
IS - 13-14
SP - 2072
EP - 2081
PB - Wiley-VCH Verlag GmbH & Co. KGaA
CY - Weinheim, Germany
AN - OPUS4-36434
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Al-Terkawi, Abdal-Azim
A1 - Scholz, G.
A1 - Prinz, Carsten
A1 - Zimathies, Annett
A1 - Emmerling, Franziska
A1 - Kemnitz, E.
T1 - Hydrated and dehydrated Ca-coordination polymers based on benzene-dicarboxylates: mechanochemical synthesis, structure refinement, and spectroscopic characterization
JF - CrystEngComm
N2 - A series of Ca-based coordination polymers were prepared mechanochemically by milling Ca(OH)2 with phthalic acid (H2oBDC), isophthalic acid (H2mBDC), and terephthalic acid (H2pBDC). The hydrated compounds [Ca(oBDC)(H2O)], [Ca(mBDC)(H2O)3.4], and [Ca(pBDC)(H2O)3] were prepared for the first time via mechanochemical routes. The refined structures were validated by extended X-ray absorption data. The new dehydrated compound [Ca(oBDC)] (1-H2O), obtained after the thermal post-treatment of 1 in a reversible phase transition process, was determined ab initio based on the powder X-ray diffraction (PXRD) data. The materials were thoroughly characterized using elemental analysis, thermal analysis, and spectroscopic methods: magic-angle spinning NMR and attenuated total reflection-infrared spectroscopy. The specific surface areas and sorption properties of the hydrated and dehydrated samples were determined using the isotherms of gas sorption and dynamic vapor sorption measurements.
KW - Mechanochemistry
KW - XRD
PY - 2018
UR - http://pubs.rsc.org/en/content/articlehtml/2017/ce/c7ce01906h
DO - https://doi.org/10.1039/C7CE01906H
VL - 20
SP - 946
EP - 961
PB - Royal Society of Chemistry
AN - OPUS4-44440
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kulla, Hannes
A1 - Haferkamp, Sebastian
A1 - Akhmetova, Irina
A1 - Röllig, Mathias
A1 - Maierhofer, Christiane
A1 - Rademann, Klaus
A1 - Emmerling, Franziska
T1 - In situ investigations of mechanochemical one-pot syntheses
JF - Angewandte Chemie International Edition
N2 - We present an in situ triple coupling of synchrotron X-ray diffraction with Raman spectroscopy, and thermography to study milling reactions in real time. This combination of methods allows a correlation of the structural evolution with temperature information. The temperature information is crucial for understanding both the thermodynamics and reaction kinetics. The reaction mechanisms of three prototypical mechanochemical syntheses, a cocrystal formation, a C@C bond formation (Knoevenagel condensation), and the formation
of a manganese-phosphonate, were elucidated. Trends in the temperature development during milling are identified. The heat of reaction and latent heat of crystallization of the product contribute to the overall temperature increase. A decrease in temperature occurs via release of, for example, water as a byproduct.
Solid and liquid intermediates are detected. The influence of the mechanical impact could be separated from temperature effects caused by the reaction.
KW - In situ studies
KW - Mechanochemistry
KW - Raman spectroscopy
KW - Thermography
KW - X-ray diffraction
PY - 2018
DO - https://doi.org/10.1002/anie.201800147
SN - 1433-7851
SN - 1521-3773
VL - 57
IS - 20
SP - 5930
EP - 5933
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-44946
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Bhattacharya, Biswajit
A1 - Witt, Julia
A1 - Jain, Mohit
A1 - Emmerling, Franziska
T1 - In situ time-resolved monitoring of mixed-ligand metal–organic framework mechanosynthesis
JF - CrystEngComm
N2 - The mechanism of mixed-ligand metal–organic framework (MOF) formation, and the possible role of intermediate single-ligand metal complexes during mechanosynthesis, have not been explored yet. For the first time, we report here in situ real-time monitoring of the mechanochemical formation mechanism of mixed-ligand MOFs. Our results show that binary phases can act as intermediates or competing products in one-pot and stepwise synthesis.
KW - Mechanochemistry
KW - Metal-organic-frameworks
KW - In situ X-ray diffraction
KW - Mixed-ligand MOFs
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-558167
DO - https://doi.org/10.1039/D2CE00803C
SP - 1
EP - 4
PB - Royal Society of Chemistry
AN - OPUS4-55816
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Schiffmann, J.
A1 - Emmerling, Franziska
A1 - Martins, Ines
A1 - Van Wüllen, L.
T1 - In-situ reaction monitoring of a mechanochemical ball mill reaction with solid state NMR
JF - Solid State Nuclear Magnetic Resonance
N2 - We present an approach towards the in situ solid state NMR monitoring of mechanochemical reactions in a ball mill. A miniaturized vibration ball mill is integrated into the measuring coil of a home-built solid state NMR probe, allowing for static solid state NMR measurements during the mechanochemical reaction within the vessel. The setup allows to quantitatively follow the product evolution of a prototypical mechanochemical reaction, the formation of zinc phenylphosphonate from zinc acetate and phenylphosphonic acid. MAS NMR investigations on the final reaction mixture confirmed a reaction yield of 89% in a typical example. Thus, NMR spectroscopy may in the future provide complementary information about reaction mechanisms of mechanochemical reactions and team up with other analytical methods which have been employed to follow reactions in situ, such as Raman spectroscopy or X-ray diffraction.
KW - Mechanochemistry
KW - Solid state NMR
KW - NMR probe Development
PY - 2020
DO - https://doi.org/10.1016/j.ssnmr.2020.101687
VL - 109
SP - 101687
PB - Elsevier Inc.
AN - OPUS4-51283
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Olivera, Paulo
A1 - Michalchuk, Adam
A1 - Marquardt, Julien
A1 - Feiler, Torvid
A1 - Prinz, Carsten
A1 - Torresi, R.
A1 - Camargo, P.
A1 - Emmerling, Franziska
T1 - Investigating the role of reducing agents on mechanosynthesis of Au nanoparticles
JF - CrystEngComm
N2 - Control over the bottom up synthesis of metal nanoparticles (NP) depends on many experimental factors, including the choice of stabilising and reducing agents. By selectively manipulating these species, it is possible to control NP characteristics through solution-phase synthesis strategies. It is not known, however, whether NPs produced from mechanochemical syntheses are governed by the same rules. Using the Au NPs mechanosynthesis as a model system, we investigate how a series of common reducing agents affect both the reduction kinetics and size of Au NPs. It is shown that the relative effects of reducing agents on mechanochemical NP synthesis differ significantly from their role in analogous solution-phase reactions. Hence, strategies developed for control over NP growth in solution are not directly transferrable to environmentally benign mechanochemical approaches. This work demonstrates a clear need for dedicated, systematic studies on NP mechanosynthesis.
KW - Mechanochemistry
KW - Metal nanoparicels
PY - 2020
DO - https://doi.org/10.1039/d0ce00826e
VL - 22
IS - 38
SP - 6261
EP - 6267
PB - Royal Society of Chemistry
AN - OPUS4-51757
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kulla, Hannes
A1 - Greiser, Sebastian
A1 - Benemann, Sigrid
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Knowing When To Stop-Trapping Metastable Polymorphs in Mechanochemical Reactions
JF - Crystal Growth and Design
N2 - The cocrystal formation of pyrazinamide (PZA) with malonic acid (MA) was studied in situ. The mechanochemical reaction proceeds via conversion of a crystalline intermediate (PZA:MA II) into the thermodynamically more stable form (PZA:MA I) upon further grinding. The information derived from in situ powder X-ray diffraction (PXRD) enabled the isolation of this new metastable polymorph. On the basis of the PXRD data, the crystal structure of the 1:1 cocrystal PZA:MA II was solved. The polymorphs were further characterized and compared by Raman spectroscopy, solid-state NMR spectroscopy, differential thermal analysis/thermogravimetric analysis, and scanning electron microscopy. Our study demonstrates how monitoring mechanochemical reactions by in situ PXRD can direct the discovery and isolation of even short-lived intermediates not yet accessed by conventional methods.
KW - Mechanochemistry
KW - Polymorphs
KW - Metastable
KW - In situ PXRD
KW - Cocrystal
KW - Pyrazinamide
PY - 2017
DO - https://doi.org/10.1021/acs.cgd.6b01572
SN - 1528-7483
SN - 1528-7505
VL - 17
IS - 3
SP - 1190
EP - 1196
AN - OPUS4-39420
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zuffa, Caterina
A1 - Cappuccino, Chiara
A1 - Casali, Lucia
A1 - Emmerling, Franziska
A1 - Maini, Lucia
T1 - Liquid reagents are not enough for liquid assisted grinding in the synthesis of (AgBr)(n-pica) n
JF - Physical Chemistry Chemical Physics
N2 - This study investigates the mechanochemical reactions between AgBr 3-picolylamine and 4-picolylamine. The use of different stoichiometry ratios of the reagents allows [(AgBr)(n-pica)]n and [(AgBr)2(n-pica)]n to be obtained, and we report the new structures of [(AgBr)2(3-pica)]n and [(AgBr)2(4-pica)]n which are characterized by the presence of the following: (a) infinite inorganic chains, (b) silver atom coordinated only by bromide atoms and (c) argentophilic interactions. Furthermore, we studied the interconversion of [(AgBr)(n-pica)]n/[(AgBr)2(n-pica)]n by mechanochemical and thermal properties. The in situ experiments suggest that [(AgBr)(3-pica)]n is kinetically favoured while [(AgBr)2(3-pica)]n is converted into [(AgBr)(3-pica)]n only with a high excess of the ligand. Finally, the liquid nature of the ligands is not sufficient to assist the grinding process, and the complete reaction is observed with the addition of a small quantity of acetonitrile.
KW - Mechanochemistry
KW - Complex
PY - 2024
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594755
DO - https://doi.org/10.1039/d3cp04791a
SN - 1463-9076
SP - 1
EP - 10
PB - Royal Society of Chemistry (RSC)
AN - OPUS4-59475
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kulla, Hannes
A1 - Michalchuk, Adam
A1 - Emmerling, Franziska
T1 - Manipulating the dynamics of mechanochemical ternary cocrystal formation
JF - ChemComm
N2 - The mechanism of ternary cocrystal formation, and the potential role of intermediate binary phases, has been debated for some time. We report here the first in situ real-time monitoring of two prototypic ternary cocrystals. Our results suggest that the question is more complicated than previously considered. The mechanism of mechanochemical ternary cocrystal formation depends on the milling conditions, here the milling frequency and addition of liquid. Binary phases can form under certain conditions, but do not act as intermediates in the formation of the ternary cocrystals. Rather, binary phases are competitive with the ternary phase, and their formation appears to compete with that of the ternary components. The presence of binary phases leads to an increase in the overall reaction time. The results reported here offer the first insights into the true complexities of mechanochemical multi-component synthesis of higher order multi-component crystals and demonstrate a new understanding of the influence of milling condition for the study of mechanisms and kinetics.
KW - Mechanochemistry
KW - In situ
KW - Cocrystal
PY - 2019
UR - https://pubs.rsc.org/en/content/articlepdf/2019/cc/c9cc03034d
DO - https://doi.org/10.1039/c9cc03034d
SN - 1364-548X
VL - 55
IS - 66
SP - 9793
EP - 9796
PB - RSC
AN - OPUS4-48613
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Bhattacharya, Biswajit
A1 - Akhmetova, Irinia
A1 - Emmerling, Franziska
T1 - Mechanochemical and solution syntheses of two novel cocrystals of orcinol with two N,N0-Dipyridines: Structural diversity with varying ligand flexibility
JF - Journal of Molecular Structure
N2 - We studied the influence of coformers flexibility on the supramolecular assembly of 5-substituted resorcinol. Two cocrystals of orcinol (ORL) with two dipyridine molecules, i.e. 1,2-di(4-pyridyl)ethane (ORLeBPE) and 1,2-di(4-pyridyl)ethylene (ORLeBPY), were prepared by mechanochemical synthesis and slow evaporation of solvent. The new crystalline solids were thoroughly characterized by single crystal Xray diffraction (SCXRD), powder X-ray diffraction analysis (PXRD), Fourier-transform infrared spectroscopy (FT-IR), differential thermal analysis (DTA), and thermogravimetric analysis (TGA). Structural determination reveals that in both cocrystals, the phenolepyridine, i.e. OeH/N(py) heterosynthon takes the main role in the formation of cocrystals. In ORLeBPE, the components form infinite 1D zig-zag chains, which are extended to 2D layer structure by inter-chain CeH/O interactions between BPE hydrogen atoms and hydroxyl oxygen atoms of ORL. In ORLeBPY, the components form a 0D fourcomponent complex. Formation of the discrete assemblies is attributed to the comparative rigid nature of BPY, which restricts the formation of an extended network.
KW - Cocrystal
KW - Single crystal
KW - X-ray diffraction
KW - Mechanochemistry
PY - 2020
DO - https://doi.org/10.1016/j.molstruc.2020.128303
SN - 0022-2860
VL - 1217
SP - 128303
PB - Elsevier B.V.
AN - OPUS4-51023
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Haferkamp, Sebastian
A1 - Fischer, Franziska
A1 - Kraus, Werner
A1 - Emmerling, Franziska
T1 - Mechanochemical Knoevenagel condensation investigated in situ
JF - Beilstein Journal of organic chemistry
N2 - The mechanochemical Knoevenagel condensation of malononitrile with p-nitrobenzaldehyde was studied in situ using a tandem approach. X-ray diffraction and Raman spectroscopy were combined to yield time-resolved information on the milling process. Under solvent-free conditions, the reaction leads to a quantitative conversion to p-nitrobenzylidenemalononitrile within 50 minutes. The in situ data indicate that the process is fast and proceeds under a direct conversion. After stopping the milling process, the reaction continues until complete conversion. The continuous and the stopped milling process both result in crystalline products suitable for single crystal X-ray diffraction.
KW - Mechanochemistry
KW - Ball milling
KW - C–C coupling
KW - In situ
KW - Knoevenagel condensation
PY - 2017
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-425388
DO - https://doi.org/10.3762/bjoc.13.197
VL - 13
SP - 2010
EP - 2014
PB - Beilstein-Institut
AN - OPUS4-42538
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Martins, I.
A1 - Carta, M.
A1 - Haferkamp, Sebastian
A1 - Feiler, Torvid
A1 - Delogu, F.
A1 - Colacino, E.
A1 - Emmerling, Franziska
T1 - Mechanochemical N‑Chlorination Reaction of Hydantoin: In Situ Real-Time Kinetic Study by Powder X‑ray Diffraction and Raman Spectroscopy
JF - Acs Sustainable Chemistry & Engineering
N2 - Mechanochemistry has become a valuable tool for the synthesis of new molecules, especially in the field of organic chemistry. In the present work, we investigate the kinetic profile of the chlorination reaction of N-3-ethyl-5,5-dimethylhydantoin (EDMH) activated and driven by ball milling. The reaction has been carried out using 2 mm, 4 mm, 5 mm, 6 mm, and 8 mm ball sizes in a new small custom-made Perspex milling jar. The Crystal structure of the starting material EDMH and the 1-chloro-3-ethyl5,5′-dimethyl hydantoin (CEDMH) chlorination product was solved by single-crystal X-ray diffraction. The reaction was monitored, in situ and in real time, by both powder X-ray diffraction (PXRD) and Raman spectroscopy. Our kinetic data show that the reaction progress to equilibrium is similar at all milling ball sizes. The induction period is very short (between 10 and 40 s) when using 4 mm, 5 mm, 6 mm, and 8 mm balls. For the reaction performed with a 2 mm ball, a significantly longer induction period of 9 min was observed. This could indicate that an initial energy accumulation and higher mixing efficiency are necessary before the reaction starts. Using different kinetic models, we found that the amount of powder affected by critical loading conditions during individual impacts is significantly dependent on the ball size used. An almost linear correlation between the rate of the chemical transformations and the ball volume is observed.
KW - Mechanochemistry
KW - In situ real-time monitoring
KW - N-Chlorination
KW - Kinetics
KW - Hydantoin
KW - Powder X-ray diffraction
KW - Raman spectroscopy
PY - 2021
DO - https://doi.org/10.1021/acssuschemeng.1c03812
VL - 9
IS - 37
SP - 12591
EP - 12601
AN - OPUS4-53541
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Souza, B.
A1 - Chauque, S.
A1 - de Oliveira, P.
A1 - Emmerling, Franziska
A1 - Torresi, R.
T1 - Mechanochemical optimization of ZIF-8/Carbon/S8 composites for lithium-sulfur batteries positive electrodes
JF - Journal of Electroanalytical Chemistry
N2 - The application of lithium-sulfur (Li-S) batteries is still limited by their rapid capacity fading. The pulverization of the sulfur positive electrode after the lithiation and the consequence dissolution of long chain polysulfides in organic solvents lead to the shuttle effect. To address these issues, here we report the mechanochemical preparation of ZIF-8 (Zeolitic Imidazole Framework-8)-based composites as sulfur hosts for positive electrodes in Li-S batteries. We studied different methods for the incorporation of conductive carbon. Also, the replacement of Zn2+ metal centers by other bivalent metals (Cu2+, Co2+ and Ni2+), enabled the preparation of other ZIF-8-based materials. The positive electrode ZIF-8/C/S8 showed initial discharges of 772 mA h g−1 while the pristine one, ZIF-8/S8, displayed 502 mA h g−1. The enhanced performance of 54% for ZIF-8/C/S8 indicates that the direct mechanochemical synthesis of ZIF-8 with conductive carbon is beneficial at initials charge/discharge process in comparison to traditional slurry preparation (ZIF-8/S8). Also, the Li2S6 absorption tests shows 87% of discoloration with ZIF-8/C/S8, confirming the better polysulfides absorption.
KW - Lithium-sulfur battery
KW - Metal organic frameworks
KW - ZIF-8
KW - Mechanochemistry
PY - 2021
DO - https://doi.org/10.1016/j.jelechem.2021.115459
VL - 896
SP - 115459
PB - Elsevier B.V.
AN - OPUS4-53542
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wilke, Manuel
A1 - Akhemtova, Irina
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Mechanochemical synthesis of cerium(IV)-phosphonates
JF - Journal of materials science
N2 - The syntheses and crystal structures of two cerium(IV) phosphonates are presented. Cerium(IV) bis(phenylphosphonate) Ce(O3PC6H5)2 1 can be formed from precipitation and mechanochemical reaction, whereas cerium(IV) bis(carboxymethylphosphonate) monohydrate Ce(O3PCH2COOH)2 H2O 2 is only accessible via ball milling. All reactions proceed very fast and are completed within a short time span. In situ measurements for the syntheses of 1 show that the product occurs within seconds or a few minutes, respectively. The structures were solved from powder X-ray diffraction data.
KW - In situ studies
KW - Mechanochemistry
KW - XRD
PY - 2018
DO - https://doi.org/10.1007/s10853-018-2507-x
SN - 0022-2461
SN - 1573-4803
VL - 53
IS - 19
SP - 13733
EP - 13741
PB - Springer Science + Business Media B.V.
AN - OPUS4-45672
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Gernhard, M.
A1 - Radnik, Jörg
A1 - Witt, Julia
A1 - Roth, C.
A1 - Emmerling, Franziska
T1 - Mechanochemical synthesis of fluorine-containing Co-doped zeolitic imidazolate frameworks for producing electrocatalysts
JF - Frontiers in chemistry
N2 - Catalysts derived from pyrolysis of metal organic frameworks (MOFs) are promising candidates to replace expensive and scarce platinum-based electrocatalysts commonly used in polymer electrolyte membrane fuel cells. MOFs contain ordered connections between metal centers and organic ligands. They can be pyrolyzed into metal- and nitrogen-doped carbons, which show electrocatalytic activity toward the oxygen reduction reaction (ORR). Furthermore, metal-free heteroatom-doped carbons, such as N-F-Cs, are known for being active as well. Thus, a carbon material with Co-N-F doping could possibly be even more promising as ORR electrocatalyst. Herein, we report the mechanochemical synthesis of two polymorphs of a zeolitic imidazole framework, Co-doped zinc 2-trifluoromethyl-1H-imidazolate (Zn0.9Co0.1(CF3-Im)2). Time-resolved in situ X-ray diffraction studies of the mechanochemical formation revealed a direct conversion of starting materials to the products. Both polymorphs of Zn0.9Co0.1(CF3-Im)2 were pyrolyzed, yielding Co-N-F containing carbons, which are active toward electrochemical ORR.
KW - Mechanochemistry
KW - Metal-organic-frameworks
KW - Nobel-metal free electrocatalysis
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546833
DO - https://doi.org/10.3389/fchem.2022.840758
SN - 2296-2646
VL - 10
IS - 840758
SP - 1
EP - 13
PB - Frontiers Media
CY - Lausanne
AN - OPUS4-54683
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Bhattacharya, Biswajit
A1 - Das, Chayanika
A1 - Emmerling, Franziska
T1 - Mechanochemical Synthesis of Phosphonate-Based Proton Conducting Metal-Organic Frameworks
JF - Inorganic Chemistry
N2 - Water-stable metal−organic frameworks (MOFs) with proton-conducting behavior have attracted great attention as promising materials for proton-exchange membrane fuel cells. Herein, we report the mechanochemical gram-scale synthesis of three new mixed-ligand phosphonate-based MOFs, {Co(H2PhDPA)(4,4′-bipy)H2O)·2H2O}n (BAM-1), {Fe(H2PhDPA)(4,4′-bipy) (H2O)·2H2O}n (BAM-2), and {Cu(H2PhDPA)(dpe)2(H2O)2·2H2O}n (BAM-3) [where H2PhDPA = phenylene diphosphonate, 4,4′-bipy = 4,4′-bipyridine, and dpe = 1,2-di(4-pyridyl)ethylene]. Single-crystal X-ray diffraction measurements revealed that BAM-1 and BAM-2 are isostructural and possess a three-dimensional (3D) network structure comprising one-dimensional (1D) channels filled with guest water molecules. Instead, BAM-3 displays a 1D network structure extended into a 3D supramolecular structure through hydrogenbonding and π−π interactions. In all three structures, guest water molecules are interconnected with the uncoordinated acidic hydroxyl groups of the phosphonate moieties and coordinated water molecules by means of extended hydrogen-bonding interactions. BAM-1 and BAM-2 showed a gradual increase in proton conductivity with increasing temperature and reached 4.9 × 10−5 and 4.4 × 10−5 S cm−1 at 90 °C and 98% relative humidity (RH). The highest proton conductivity recorded for BAM-3 was 1.4 × 10−5 S cm−1 at 50 °C and 98% RH. Upon further heating, BAM-3 undergoes dehydration followed by a phase transition to another crystalline form which largely affects its performance. All compounds exhibited a proton hopping (Grotthuss model) mechanism, as suggested by their low activation energy.
KW - Mechanochemistry
KW - Metal-organic-frameworks
KW - Proton conductivity
PY - 2022
DO - https://doi.org/10.1021/acs.inorgchem.2c01023
VL - 61
SP - 10801
EP - 10809
PB - ACS Publications
AN - OPUS4-55448
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Al-Terkawi, Abdal-Azim
A1 - Scholz, G.
A1 - Emmerling, Franziska
A1 - Kemnitz, E.
T1 - Mechanochemical synthesis, characterization, and structure determination of new alkaline earth metal-tetrafluoroterephthalate frameworks: Ca(pBDC‑F4 )·4H2O, Sr(pBDC‑F4 )·4H2O, and Ba(pBDC‑F4 )
JF - Crystal Growth & Design
N2 - New fluorinated alkaline earth metal−organic frameworks were successfully synthesized by milling of metal hydroxides M(OH)2 with tetrafluoroterephthalic acid H2 pBDC-F4. Both calcium- and strontium-tetrafluoroterephthalates are tetrahydrated, while the barium tetrafluoroterephthalate is free of coordinating water molecules. The two isomorphic structures Ca(pBDC-F4)·4H2O and Sr(pBDC-F4)·4H2O were solved from the powder diffraction data by ab initio structure determination and subsequent Rietveld refinement. The products were thoroughly characterized by elemental analysis, thermal analysis, magicangle spinning NMR, Fourier transform infrared spectroscopy, scanning electron microscopy imaging, and Brunauer−Emmett−Teller measurements. Our findings suggest that the mechanochemical synthesis route is a promising approach for the preparation of new fluorinated alkaline earth metal−organic frameworks.
KW - Mechanochemistry
KW - MOFs
KW - XRD
PY - 2016
UR - http://pubs.acs.org/doi/abs/10.1021/acs.cgd.5b01457
DO - https://doi.org/10.1021/acs.cgd.5b01457
SN - 1528-7483
VL - 16/4
SP - 1923
EP - 1933
PB - American Chemical Society
CY - Washington, DC, USA
AN - OPUS4-35940
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fischer, Franziska
A1 - Greiser, Sebastian
A1 - Peifer, Dietmar
A1 - Jäger, Christian
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Mechanochemically Induced Conversion of Crystalline Benzamide Polymorphs by Seeding
JF - Angewandte Chemie International Edition
N2 - Benzamide has been known for its polymorphism for almost 200 years.Three polymorphic forms are described. To date,itwas only possible to crystallizeametastable form in amixture together with the thermodynamically most stable form I. Acomplete transformation of form Iinto the metastable form III by mechanochemical treatment has been achieved. Catalytic amounts of nicotinamide seeds were used to activate the conversion by mechanochemical seeding. NMR experiments indicated that the nicotinamide molecules were incorporated statistically in the crystal lattice of benzamide form III during the conversion. The transformation pathway was evaluated using in situ powder X-ray diffraction.
KW - Nicotinamide
KW - Benzamide
KW - In situ reactions
KW - Mechanochemistry
KW - Polymorphs
PY - 2016
DO - https://doi.org/10.1002/anie.201607358
VL - 128
IS - 46
SP - 14493
EP - 14497
PB - WILEY-VCH
CY - Weinheim
AN - OPUS4-38472
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gugin, Nikita
A1 - Villajos Collado, José Antonio
A1 - Feldmann, Ines
A1 - Emmerling, Franziska
T1 - Mix and wait – a relaxed way for synthesizing ZIF-8
JF - RSC Advances
N2 - Herein we report the synthesis of a zeolitic imidazolate framework (ZIF-8) by an easy “mix and wait” procedure. In a closed vial, without any interference, the mixture of 2-methylimidazole and basic zinc carbonate assembles into the crystalline product with approx. 90% conversion after 70 h. The reaction exhibits sigmoidal kinetics due to the self-generated water which accelerates the reaction.
KW - In-situ analysis
KW - Mechanochemistry
KW - MOF
KW - Synthesis
KW - ZIF-8
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-546841
DO - https://doi.org/10.1039/D2RA00740A
VL - 12
SP - 8940
EP - 8944
PB - Royal Society of Chemistry
AN - OPUS4-54684
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Opitz, P.
A1 - Asta, M.
A1 - Fernandez-Martinez, A.
A1 - Panthöfer, M.
A1 - Kabelitz, Anke
A1 - Emmerling, Franziska
A1 - Mondeshki, M.
A1 - Tremel, W.
T1 - Monitoring a Mechanochemical Syntheses of Isostructural Luminescent Cocrystals of 9-Anthracenecarboxylic Acid with two Dipyridines Coformers
JF - Crystal Growth and Design
N2 - Amorphous calcium carbonate (ACC) is an important precursor in the biomineralization of crystalline CaCO3. In nature, it serves as a storage material or as a permanent structural element, whose lifetime is regulated by an organic matrix. The relevance of ACC in materials science is primarily related to our understanding of CaCO3 crystallization pathways and CaCO3/(bio)polymer nanocomposites. ACC can be synthesized by liquid–liquid phase separation, and it is typically stabilized with macromolecules. We have prepared ACC by milling calcite in a planetary ball mill. Phosphate “impurities” were added in the form of monetite (CaHPO4) to substitute the carbonate anions, thereby stabilizing ACC by substitutional disorder. The phosphate anions do not simply replace the carbonate anions. They undergo shear-driven acid/base and condensation reactions, where stoichiometric (10%) phosphate contents are required for the amorphization to be complete. The phosphate anions generate a strained network that hinders ACC recrystallization kinetically. The amorphization reaction and the structure of BM-ACC were studied by quantitative Fourier transform infrared spectroscopy and solid state 31P, 13C, and 1H magic angle spinning nuclear magnetic resonance spectroscopy, which are highly sensitive to symmetry changes of the local environment. In the first—and fast—reaction step, the CO32– anions are protonated by the HPO42– groups. The formation of unprecedented hydrogen carbonate (HCO3–) and orthophosphate anions appears to be the driving force of the reaction, because the phosphate group has a higher Coulomb energy and the tetrahedral PO43– unit can fill space more efficiently. In a competing second—and slow—reaction step, pyrophosphate anions are formed in a condensation reaction. No pyrophosphates are formed at higher carbonate contents. High strain leads to such a large energy barrier that any reaction is suppressed. Our findings aid in the understanding of the mechanochemical amorphization of calcium carbonate and emphasize the effect of impurities for the stabilization of the amorphous phases in general. Our approach allowed the synthesis of new amorphous alkaline earth defect variants containing the unique HCO3– anion. Our approach outlines a general strategy to obtain new amorphous solids for a variety of carbonate/phosphate systems that offer promise as biomaterials for bone regeneration.
KW - Crystallization
KW - Mechanochemistry
KW - PDF
PY - 2020
DO - https://doi.org/10.1021/acs.cgd.0c00912
VL - 20
IS - 10
SP - 6831
EP - 6846
PB - American Chemical Society
AN - OPUS4-51819
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zänker, Steffen
A1 - Scholz, G.
A1 - Heise, M.
A1 - Kemnitz, E.
A1 - Emmerling, Franziska
T1 - New 2D layered structures with direct fluorine-metal bonds: MF(CH3COO) (M: Sr, Ba, Pb)
JF - CrystEngComm
N2 - New coordination polymers with 2D network structures with fluorine directly coordinated to the metal ion were prepared both via mechanochemical synthesis and fluorolytic sol–gel synthesis. Depending on the synthesis route, the samples show different particle sizes, according to SEM imaging. The crystal structures of barium acetate fluoride, strontium acetate fluoride, and lead acetate fluoride (BaFIJCH3COO), SrFIJCH3COO) and PbFIJCH3COO)) were solved from X-ray powder diffraction data. The structure solution is backed by the results from 19F MAS NMR, FT IR data, and thermal analysis. The calculated chemical shifts of the 19F MAS NMR spectra coincide well with the measured ones. It turns out that the grinding conditions have a remarkable influence on the mechanochemical synthesis and its products. Our systematic study also indicates a strong influence of the atomic radii of Ca, Sr, Ba, and Pb on the success of the syntheses.
KW - Mechanochemistry
KW - Coordination polymers
PY - 2020
DO - https://doi.org/10.1039/d0ce00287a
VL - 22
IS - 16
SP - 2772
EP - 2780
PB - Royal Society of Chemistry
AN - OPUS4-50789
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Mazzeo, P. P.
A1 - Prencipe, M.
A1 - Feiler, Torvid
A1 - Emmerling, Franziska
A1 - Bacchi, A.
T1 - On the mechanism of cocrystal mechanochemical reaction via low melting eutectic: A time-resolved in situ monitoring investigation
JF - Crystal growth and design
N2 - Mechanochemistry has become a sustainable and attractive cost-effective synthetic technique, largely used within the frame of crystal engineering. Cocrystals, namely, crystalline compounds made of different chemical entities within the same crystal structure, are typically synthesized in bulk via mechanochemistry; however, whereas the macroscopic aspects of grinding are becoming clear, the fundamental principles that underlie mechanochemical cocrystallization at the microscopic level remain poorly understood. Time-resolved in situ (TRIS) monitoring approaches have opened the door to exceptional detail regarding mechanochemical reactions. We here report a clear example of cocrystallization between two solid coformers that proceeds through the formation of a metastable low melting binary eutectic phase. The overall cocrystallization process has been monitored by time-resolved in situ (TRIS) synchrotron X-ray powder diffraction with a customized ball milling setup, currently available at μ Spot beamline at BESSY-II, Helmholtz-Zentrum Berlin. The binary system and the low melting eutectic phase were further characterized via DSC, HSM, and VT-XRPD.
KW - Mechanochemistry
KW - In situ
KW - Cocrystal
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-552977
DO - https://doi.org/10.1021/acs.cgd.2c00262
SN - 1528-7505
VL - 22
IS - 7
SP - 4260
EP - 4267
PB - ACS Publ.
CY - Washington, DC
AN - OPUS4-55297
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Tumanova, N.
A1 - Tumanov, N.
A1 - Robeyns, K.
A1 - Fischer, Franziska
A1 - Fusaro, L.
A1 - Morelle, F.
A1 - Ban, V.
A1 - Hautier, G.
A1 - Filinchuk, Y.
A1 - Wouters, J.
A1 - Leyssens, T.
A1 - Emmerling, Franziska
T1 - Opening Pandora’s Box: Chirality, Polymorphism, and Stoichiometric Diversity in Flurbiprofen/Proline Cocrystals
JF - Crystal Growth & Design
N2 - Proline has been widely used for various cocrystallization applications, including pharmaceutical cocrystals. Combining enantiopure and racemic flurbiprofen and proline, we discovered 18 new crystal structures. Liquid-assisted grinding proved highly efficient to explore all the variety of crystal forms. A unique combination of stateof-the-art characterization techniques, comprising variable temperature in situ X-ray diffraction and in situ ball-milling, along with other physicochemical methods and density functional theory calculations, was indispensable for identifying all the phases. Analyzing the results of in situ ball-milling, we established a stepwise mechanism for the formation of several 1:1 cocrystals via an intermediate 2:1 phase. The nature of the solvent in liquidassisted grinding was found to significantly affect the reaction rate and, in some cases, the reaction pathway.
KW - Mechanochemistry
KW - Polymorphs
KW - In situ
PY - 2018
UR - https://pubs.acs.org/doi/abs/10.1021/acs.cgd.7b01436
DO - https://doi.org/10.1021/acs.cgd.7b01436
VL - 18
IS - 2
SP - 954
EP - 961
PB - American Chemical Society
AN - OPUS4-44365
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Gugin, Nikita
A1 - Villajos Collado, José Antonio
A1 - Dautain, O.
A1 - Maiwald, Michael
A1 - Emmerling, Franziska
T1 - Optimizing the Green Synthesis of ZIF-8 by Reactive Extrusion Using In Situ Raman Spectroscopy
JF - ACS Sustainable Chemistry & Engineering
N2 - We report the scale-up of a batch solid synthesis of zeolitic imidazolate framework-8 (ZIF-8) for reactive extrusion. The crystalline product forms in the extruder directly under the mixture of solid 2-methylimidazole and basic zinc carbonate in the presence of a catalytic amount of liquid. The process parameters such as temperature, liquid type, feeding rate, and linker excess were optimized using the setup specifically designed for in situ Raman spectroscopy. Highly crystalline ZIF-8 with a Brunauer–Emmett–Teller (BET) surface area of 1816 m2 g–1 was quantitatively prepared at mild temperature using a catalytic amount of ethanol and a small excess of the linker. Finally, we developed a simple and comprehensive approach to evaluating the environmental friendliness and scalability of metal–organic framework (MOF) syntheses in view of their large-scale production.
KW - Mechanochemistry
KW - In situ Raman
KW - Large-scale processing
KW - Metal−organic frameworks
KW - Twin-screw extrusion (TSE)
PY - 2023
DO - https://doi.org/10.1021/acssuschemeng.2c07509
SN - 2168-0485
VL - 11
IS - 13
SP - 5175
EP - 5183
PB - ACS Publications
AN - OPUS4-57366
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Belenguer, A.
A1 - Lampronti, G.
A1 - Michalchuk, Adam
A1 - Emmerling, Franziska
A1 - Sanders, J.
T1 - Quantitative reversible one pot interconversion of three crystalline polymorphs by ball mill grinding
JF - Crystengcomm
N2 - We demonstrate here using a disulfide system the first example of reversible, selective, and quantitative transformation between three crystalline polymorphs by ball mill grinding. This includes the discovery of a previously unknown polymorph. Each polymorph is reproducibly obtained under well-defined neat or liquid-assisted grinding conditions, revealing subtle control over the apparent thermodynamic stability. We discovered that the presence of a contaminant as low as 1.5% mol mol−1 acting as a template is required to enable all these three polymorph transformations. The relative stabilities of the polymorphs are determined by the sizes of the nanocrystals produced under different conditions and by surface interactions with small amounts of added solvent. For the first time, we show evidence that each of the three polymorphs is obtained with a unique and reproducible crystalline size. This mechanochemical approach gives access to bulk quantities of metastable polymorphs that are inaccessible through recrystallisation.
KW - Mechanochemistry
KW - Polymorph
KW - XRD
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-549934
DO - https://doi.org/10.1039/D2CE00393G
SP - 1
EP - 7
PB - Royal Society of Chemistry
AN - OPUS4-54993
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Al-Terkawi, Abdal-Azim
A1 - Scholz, G.
A1 - Emmerling, Franziska
A1 - Kemnitz, E.
T1 - Strontium-coordination polymers based on tetrafluorophthalic and phthalic acids: mechanochemical synthesis, ab initio structures determination, and spectroscopic characterization
JF - Dalton transactions
N2 - Two strontium-based dicarboxylate systems [Sr(oBDC-F4)(H2O)2] (1) and [{Sr(oBDC)(H2O)2)·H2O] (2) were synthesized mechanochemically via milling of Sr(OH)2·8H2O with tetrafluorophthalic acid (H2oBDC-F4) or phthalic acid (H2oBDC), respectively. The new structures were determined ab initio from the powder X-ray diffraction (PXRD) data. Both compounds 1 and 2 crystallize in the monoclinic space group P21 /c as two-dimensional coordination polymers (2D-CPs). The determined structures were validated by extended X-ray absorption (EXAFS) data. Compounds 1 and 2 show different thermal stabilities. The fluorinated CP 1 is decomposed at 300 °C while the nonfluorinated CP 2 transforms into a new phase after thermal treatment at 400 °C. The two hydrated CPs exhibit small surface areas which increase after the thermal posttreatment for 1 but remains unchanged for the dehydrated sample of 2. Dynamic vapor sorption (DVS) experiments indicate that both the dehydrated and hydrated samples of 2 depict no significant differences in their adsorption isotherms. The DVS of water indicates that the phase transition after thermal posttreatment of 2 is irreversible.
KW - Mechanochemistry
KW - XRD
KW - NMR
PY - 2017
DO - https://doi.org/10.1039/c7dt02564e
SN - 1477-9226
SN - 1477-9234
VL - 46
IS - 37
SP - 12574
EP - 12587
PB - The Royal Society of Chemistry
CY - Cambridge
AN - OPUS4-42261
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Zänker, Steffen
A1 - Scholz, G.
A1 - Marquardt, Julien
A1 - Emmerling, Franziska
T1 - Structural changes in Ba-compounds of different hardness induced by high-energy ball milling – evidenced by 137Ba NMR and X-ray powder diffraction
JF - Zeitschrift für anorganische und allgemeine Chemie
N2 - Changes in the global bulk and local structures, of three different barium compounds (BaZrO3, BaF2, and BaFCl),were induced by mechanical milling and followed using X-ray powder diffraction (PXRD), subsequent microstructure analysis, and 137Ba solid state NMR spectroscopy. Harder materials like BaZrO3 experience significantly higher structural changes upon milling than softer materials like BaF2. Moreover, soft materials with layered structures, like BaFCl, show a pronounced structural change during the milling process. By combining PXRD and solid state NMR, detailed information on the changes to the global and local structures were obtained, which are of interest for mechanochemical synthesis, mechanically treated catalysts or ionic conductors.
KW - Mechanochemistry
KW - X-ray diffraction
KW - Solid state NMR
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-547397
DO - https://doi.org/10.1002/zaac.202200026
SN - 0044-2313
VL - 648
IS - 10
SP - 1
EP - 8
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-54739
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Emmerling, Franziska
A1 - Haferkamp, Sebastian
A1 - Kraus, Werner
T1 - Studies on the mechanochemical Knoevenagel condensation of fluorinated benzaldehyde derivates
JF - Journal of Materials Science
N2 - The mechanochemical Knoevenagel condensation of three fluorinated benzaldehyde derivates and malononitrile was investigated. The reactions were performed under solvent- and catalyst-free conditions and resulted in highly crystalline products after crystallization from a viscous phase in the milling jar.
The quality of the obtained crystals was sufficient for single-crystal X-ray diffraction circumventing a recrystallization step. To gain more information on the reaction, progress was investigated in situ using time-resolved Raman spectroscopy. The results show a direct conversion of the reactants.
KW - C-C coupling
KW - Knoevenagel condensation
KW - In situ
KW - Mechanochemistry
PY - 2018
DO - https://doi.org/10.1007/s10853-018-2492-0
SN - 0022-2461
VL - 53
IS - 19
SP - 13713
EP - 13718
PB - Springer Link
AN - OPUS4-45682
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Fischer, Franziska
A1 - Lubjuhn, Dominik
A1 - Greiser, Sebastian
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Supply and demand in the ball mill: competitive cocrystal reactions
JF - Crystal Growth & Design
N2 - The stability of different theophylline cocrystals under milling conditions was investigated by competitive cocrystal reactions. To determine the most stable cocrystal form under milling conditions, the active pharmaceutical ingredient theophylline was either ground with two similar coformers (benzoic acid, benzamide, or isonicotinamide), or the existing theophylline cocrystals were ground together with a competitive coformer. All competitive reactions were investigated by in situ powder X-ray diffraction disclosing the formation pathway of the milling processes. On the basis of these milling reactions, a stability order (least to most stable) was derived: tp/bs < tp/ba < tp/ina < bs/ina.
KW - Mechanochemistry
KW - Cocrystal
KW - Milling
PY - 2016
DO - https://doi.org/10.1021/acs.cgd.6b00928
SN - 1528-7483
SN - 1528-7505
VL - 16
IS - 10
SP - 5843
EP - 5851
AN - OPUS4-38097
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Rautenberg, Max
A1 - Akhmetova, Irina
A1 - Das, Chayanika
A1 - Bhattacharya, Biswajit
A1 - Emmerling, Franziska
T1 - Synthesis and In Situ Monitoring of Mechanochemical Preparation of Highly Proton Conductive Hydrogen-Bonded Metal Phosphonates
JF - ACS Omega
N2 - Crystalline porous materials are recognized as promising proton conductors for the proton exchange membrane (PEM) in fuel cell technology owing to their tunable framework structure. However, it is still a challenging bulk synthesis for real-world applications of these materials. Herein, we report the mechanochemical gram-scale synthesis of two isostructural metal hydrogen-bonded organic frameworks (MHOFs) of Co(II) and Ni(II) based on 1-hydroxyethylidenediphosphonic acid (HEDPH4) with 2,2′-bipyridine (2,2′-bipy): Co(HEDPH3)2(2,2′-bipy)·H2O (1) and Ni(HEDPH3)2(2,2′-bipy)·H2O (2). In situ monitoring of the mechanochemical synthesis using different synchrotron-based techniques revealed a one-step mechanism – the starting materials are directly converted to the product. With the existence of extensive hydrogen bonds with amphiprotic uncoordinated phosphonate hydroxyl and oxygen atoms, both frameworks exhibited proton conduction in the range of 10–4 S cm–1 at room temperature under humid conditions. This study demonstrates the potential of green mechanosynthesis for bulk material preparation of framework-based solid-state proton conductors.
KW - Mechanochemistry
KW - Proton conductivity
KW - Metal Organic Frameworks
PY - 2023
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-577777
DO - https://doi.org/10.1021/acssuschemeng.2c07509
VL - 8
IS - 19
SP - 16687
EP - 16693
PB - ACS Publications
AN - OPUS4-57777
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Akhmetova, Irina
A1 - Schuzjajew, K.
A1 - Wilke, M.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Rademann, K.
A1 - Roth, C.
A1 - Emmerling, Franziska
T1 - Synthesis, characterization and in situ monitoring of the mechanochemical reaction process of two manganese(II)-phosphonates with N-containing ligands
JF - Journal of Materials Science
N2 - Two divalent manganese aminophosphonates, manganese mono (nitrilotrimethylphosphonate) (MnNP3) and manganese bis N-(carboxymethyl)iminodi(methylphosphonate)) (Mn(NP2AH)2), have been prepared by mechanochemical synthesis and characterized by powder X-ray diffraction (PXRD). The structure of the novel compound Mn(NP2AH)2 was determined from PXRD data. MnNP3 as well as Mn(NP2AH)2 exhibits a chain-like structure.
In both cases, the manganese atom is coordinated by six oxygen atoms in a distorted octahedron. The local coordination around Mn was further characterized by extended X-ray absorption fine structure. The synthesis process was followed in situ by synchrotron X-ray diffraction revealing a three-step reaction mechanism. The asprepared manganese(II) phosphonates were calcined on air.
All samples were successfully tested for their suitability as catalyst material in the oxygen evolution reaction.
KW - Mechanochemistry
KW - In situ
KW - XRD
PY - 2018
DO - https://doi.org/10.1007/s10853-018-2608-6
SN - 0022-2461
SN - 1573-4803
VL - 53
IS - 19
SP - 13390
EP - 13399
PB - Springer Science + Business Media B.V.
AN - OPUS4-45673
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - de Olivera, Paulo
A1 - Michalchuk, Adam
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Bienert, Ralf
A1 - Torresi, R.
A1 - Camargo, P.
A1 - Emmerling, Franziska
T1 - Tandem X-ray absorption spectroscopy and scattering for in situ time-resolved monitoring of gold nanoparticle mechanosynthesis
JF - ChemComm
N2 - Current time-resolved in situ approaches limit the scope of mechanochemical investigations possible. Here we develop a new, general approach to simultaneously follow the evolution of bulk atomic and electronic structure during a mechanochemical synthesis. This is achieved by coupling two complementary synchrotron-based X-ray methods: X-ray absorption spectroscopy (XAS) and X-ray diffraction. We apply this method to investigate the bottom-up mechanosynthesis of technologically important Au micro and nanoparticles in the presence of three different reducing agents, hydroquinone, sodium citrate, and NaBH4. Moreover, we show how XAS offers new insight into the early stage generation of growth species (e.g. monomers and clusters), which lead to the subsequent formation of nanoparticles. These processes are beyond the detection capabilities of diffraction methods. This combined X-ray approach paves the way to new directions in mechanochemical research of advanced electronic materials.
KW - Mechanochemistry
KW - XANES
KW - X-ray diffraction
KW - Nano particles
PY - 2020
DO - https://doi.org/10.1039/d0cc03862h
SN - 1364-548X
VL - 56
SP - 10329
EP - 10332
PB - Royal Society of Chemistry
AN - OPUS4-51760
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wilke, Manuel
A1 - Kabelitz, Anke
A1 - Gorelik, T. E.
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Reinholz, Uwe
A1 - Kolb, U.
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - The crystallisation of copper(II) phenylphosphonates
JF - Dalton Transactions
N2 - The crystal structures and syntheses of four different copper(II) phenylphosphonates, the monophenylphosphonates α-, β-, and γ-Cu(O3PC6H5)·H2O (α-CuPhPmH (1) β-CuPhPmH (2) and γ-CuPhPmH (3)), and the diphosphonate Cu(HO3PC6H5)2·H2O (CuPhP2mH (4)), are presented. The compounds were synthesized from solution at room temperature, at elevated temperature, under hydrothermal conditions, and mechanochemical conditions. The structures of α-CuPhPmH (1) and CuPhP2mH (4) were solved from powder X-ray diffraction data. The structure of β-CuPhPmH (2) was solved by single crystal X-ray analysis. The structures were validated by extended X-ray absorption fine structure (EXAFS) and DTA analyses. Disorder of the crystal structure was elucidated by electron diffraction. The relationship between the compounds and their reaction pathways were investigated by in situ synchrotron measurements.
KW - Mechanochemistry
KW - Metal phosphonate
KW - In situ
PY - 2016
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-384217
DO - https://doi.org/10.1039/C6DT02904C
SN - 1477-9226
SN - 1477-9234
VL - 45
IS - 43
SP - 17453
EP - 17463
PB - The Royal Society of Chemistry
AN - OPUS4-38421
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Michalchuk, Adam
T1 - The Mechanochemical Excitation of Crystalline LiN3
JF - Faraday Discussions
N2 - Mechanochemical reactions are driven by the direct absorption of mechanical energy by a solid (often crystalline) material. Understanding how this energy is absorbed and ultimately causes a chemical transformation is essential for understanding the elementary stages of mechanochemical transformations. Using as a model system the energetic material LiN3 we here consider how vibrational energy flows through the crystal structure. By considering the compression response of the crystalline material we identify the partitioning of energy into an initial vibrational excitation. Subsequent energy flow is based on concepts of phonon–phonon scattering, which we calculate within a quasi-equilibrium model facilitated by phonon scattering data obtained from Density Functional Theory (DFT). Using this model we demonstrate how the moments (picoseconds) immediately following mechanical impact lead to significant thermal excitation of crystalline LiN3, sufficient to drive marked changes in its electronic structure and hence chemical reactivity. This work paves the way towards an ab initio approach to studying elementary processes in mechanochemical reactions involving crystalline solids.
KW - Energetic materials
KW - Ab initio simulation
KW - DFT
KW - Mechanochemistry
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-559310
DO - https://doi.org/10.1039/d2fd00112h
SP - 1
EP - 20
PB - Royal Society of Chemistry
AN - OPUS4-55931
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Wilke, Manuel
A1 - de Oliveira Guilherme Buzanich, Ana
A1 - Reinholz, Uwe
A1 - Rademann, Klaus
A1 - Emmerling, Franziska
T1 - The structure and in situ synthesis investigation of isomorphic mononuclear molecular metal phenylphosphonates
JF - Dalton Transactions
N2 - We describe a fast and effective synthesis for molecular metal phosphonates. Isomorphic compounds [M(II)(HO₃PPh)₂(H₂O₃PPh)₂(H₂O)₂] (M = Mn (1), Co (2), Ni (3); Ph = C₆H₅) were obtained by grinding. The complexes are mononuclear compounds containing neutral and monodeprotonated phenylphosphonic acid and water as ligands. The crystal structures were determined using powder X-ray diffraction (PXRD) data and validated by extended X-ray absorption fine structure (EXAFS) data. Combined synchrotron XRD measurements and Raman spectroscopy were conducted for investigating the reactions in situ. Based on these data, the intermediates were characterized and the formation mechanism was derived.
KW - Mechanochemistry
KW - Metal phosphonate
KW - In situ
KW - XRD
PY - 2016
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-363944
DO - https://doi.org/10.1039/c6dt00787b
SN - 1477-9226
SN - 1477-9234
SN - 1364-5447
VL - 45
IS - 23
SP - 9460
EP - 9467
AN - OPUS4-36394
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Michalchuk, Adam
A1 - Emmerling, Franziska
T1 - Time-Resolved InSitu Monitoring of Mechanochemical Reactions
JF - Angewandte Chemie International Edition
N2 - Mechanochemical transformations offer environmentally benign synthesis routes, whilst enhancing both the speed and selec-tivity of reactions. In this light, mechanochemistry promises to trans-form the way in which chemistry is done in both academia and indus-try but is greatly hindered by a current lack in mechanistic understand-ing. The continued development and use of time-resolved in situ(TRIS) approaches to monitor mechanochemical reactions provides a new dimension to elucidatethese fascinating transformations. We here discuss recent trends in method development that have pushed the boundaries of mechanochemical research. New features of mech-anochemical reactions obtained by TRIS techniques are subse-quently discussed, shedding light on how different TRISapproaches have beenused. Emphasis is placed on the strength of combining complementary techniques. Finally, we outline our views for the po-tential of TRIS methods in mechanochemical research, towards es-tablishing a new, environmentally benign paradigm in the chemical sciences
KW - Mechanochemistry
KW - Material synthesis
KW - Green chemistry
PY - 2022
DO - https://doi.org/10.1002/anie.202117270
SN - 1433-7851
SP - 1
EP - 15
PB - Wiley-VCH
CY - Weinheim
AN - OPUS4-54321
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Casali, C.
A1 - Feiler, Torvid
A1 - Heilmann, Maria
A1 - Braga, D.
A1 - Emmerling, Franziska
A1 - Grepioni, F.
T1 - Too much water? Not enough? In situ monitoring of the mechanochemical reaction of copper salts with dicyandiamide
JF - CrystEngComm
N2 - n situ monitoring of mechanochemical reactions between dicyandiamide (DCD) and CuX2 salts (X = Cl−, NO3−), for the preparation of compounds of agrochemical interest, showed the appearance of a number of phases. It is demonstrated that milling conditions, such as the amount of water added in wet grinding and/or the milling frequency, may affect the course of the mechanochemical reactions, and drive the reaction towards the formation of different products. It has been possible to discover by in situ monitored experiments two novel crystalline forms, namely the neutral complexes [Cu(DCD)2(OH2)2(NO3)2] (2) and [Cu(DCD)2(OH2)Cl2]·H2O (4), in addition to the previously known molecular salt [Cu(DCD)2(OH2)2][NO3]2·2H2O (1, DIVWAG) and neutral complex [Cu(DCD)2(OH2)Cl2] (3, AQCYCU), for which no synthesis conditions were available. Compounds 2 and 4 were fully characterized via a combination of solid-state techniques, including X-ray diffraction, Raman spectroscopy and TGA.
KW - Mechanochemistry
KW - In situ
PY - 2022
DO - https://doi.org/10.1039/d1ce01670a
VL - 24
IS - 6
SP - 1292
EP - 1298
PB - RSC
AN - OPUS4-54344
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Michalchuk, Adam
A1 - Boldyreva, E.
A1 - Belenguer, A. M.
A1 - Emmerling, Franziska
A1 - Boldyrev, V. V.
T1 - Tribochemistry, mechanical alloying, mechanochemistry: what is in a name?
JF - Frontiers in chemistry
N2 - Over the decades, the application of mechanical force to influence chemical reactions has been called by various names: mechanochemistry, tribochemistry, mechanical alloying, to name but a few. The evolution of these terms has largely mirrored the understanding of the field. But what is meant by these terms, why have they evolved, and does it really matter how a process is called? Which parameters should be defined to describe unambiguously the experimental conditions such that others can reproduce the results, or to allow a meaningful comparison between processes explored under different conditions? Can the information on the process be encoded in a clear, concise, and self-explanatory way? We address these questions in this Opinion contribution, which we hope will spark timely and constructive discussion across the international mechanochemistry community.
KW - Mechanochemistry
KW - Tribochemistry
KW - Mechanical alloying
KW - Tribology
KW - Mechanical activation
KW - Nomenclature
KW - Mechanochemical pictographs
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-523291
DO - https://doi.org/10.3389/fchem.2021.685789
SN - 2296-2646
VL - 9
SP - 1
EP - 29
PB - Frontiers Media
CY - Lausanne
AN - OPUS4-52329
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Feiler, Torvid
A1 - Bhattacharya, Biswajit
A1 - Michalchuk, Adam
A1 - Rhim, S.-Y.
A1 - Schöder, V.
A1 - List-Kratochvil, E.
A1 - Emmerling, Franziska
T1 - Tuning the mechanical flexibility of organic molecular crystals by polymorphism for flexible optical waveguides
JF - CrystEngComm
N2 - The ability to selectively tune the optical and the mechanical properties of organic molecular crystals offers a promising approach towards developing flexible optical devices. These functional properties are sensitive to crystallographic packing features and are hence expected to vary with polymorphic modification. Using as a model system the photoluminescent material 4-bromo-6-[(6-chloropyridin-2-ylimino)methyl]phenol (CPMBP), we herein demonstrate the simultaneous tuning of mechanical flexibility and photoluminescence properties via polymorphism. Two new polymorphic forms of CPMBP were obtained from a solution and fully characterised using a combination of experiments and density functional theory simulations. These polymorphic forms exhibit remarkably distinct mechanical properties and an order of magnitude difference in photoluminescence quantum yield. The mechanically plastic form has a higher quantum yield than the brittle polymorphic form. However, their photoluminescence emission profile is largely unaffected by the observed polymorphism, thereby demonstrating that the optical properties and bulk mechanical properties can in principle be tuned independently. By distinguishing between active (involving absorption and emission) and passive (involving no absorption) light propagation, the waveguiding properties of the plastic form of CPMBP (form II) were explored using the straight and bent crystals to highlight the potential applications of CPMBP in designing flexible optical devices. Our results demonstrated that polymorph engineering would be a promising avenue to achieve concurrent modulation of the optical and mechanical properties of photoluminescent molecular crystals for next-generation flexible optical device applications.
KW - Mechanochemistry
KW - Flexible
PY - 2021
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-532075
DO - https://doi.org/10.1039/d1ce00642h
VL - 23
IS - 34
SP - 5815
EP - 5825
PB - Royal Society of Chemistry
CY - London
AN - OPUS4-53207
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Belenguer, A.
A1 - Michalchuk, Adam
A1 - Lampronti, G
A1 - Sanders, J
T1 - Understanding the unexpected effect of frequency on the kinetics of a covalent reaction under ball-milling conditions
JF - Beilstein journal of organic chemistry
N2 - We here explore how ball-mill-grinding frequency affects the kinetics of a disulfide exchange reaction. Our kinetic data show that the reaction progress is similar at all the frequencies studied (15–30 Hz), including a significant induction time before the nucleation and growth process starts. This indicates that to start the reaction an initial energy accumulation is necessary. Other than mixing, the energy supplied by the mechanical treatment has two effects: (i) reducing the crystal size and (ii) creating defects in the structure. The crystal-breaking process is likely to be dominant at first becoming less important later in the process when the energy supplied is stored at the molecular level as local crystal defects. This accumulation is taken here to be the rate-determining step. We suggest that the local defects accumulate preferentially at or near the crystal surface. Since the total area increases exponentially when the crystal size is reduced by the crystal-breaking process, this can further explain the exponential dependence of the onset time on the milling frequency.
KW - Mechanochemistry
KW - Kinetics
KW - Diffraction
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-483361
DO - https://doi.org/10.3762/bjoc.15.120
SN - 2195-951X
VL - 15
SP - 1226
EP - 1235
PB - Beilstein-Institut zur Förderung der Chemischen Wissenschaften
CY - Frankfurt, M.
AN - OPUS4-48336
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Haferkamp, Sebastian
A1 - Paul, Andrea
A1 - Michalchuk, Adam
A1 - Emmerling, Franziska
T1 - Unexpected polymorphism during a catalyzed mechanochemical Knoevenagel condensation
JF - Beilstein Journal of Organic Chemistry
N2 - The transformation of a base-catalyzed, mechano-assisted Knoevenagel condensation of mono-fluorinated benzaldehyde derivatives (p-, m-, o-benzaldehyde) with malonodinitrile was investigated in situ and in real time. Upon milling, the para-substituted product was found to crystallize initially into two different polymorphic forms, depending on the quantity of catalyst used. For low catalyst concentrations, a mechanically metastable phase (monoclinic) was initially formed, converting to the mechanically stable phase (triclinic) upon further grinding. Instead, higher catalyst concentrations crystallize directly as the triclinic product. Inclusion of catalyst in the final product, as evidenced by mass spectrometric analysis, suggests this complex polymorphic pathway may be due to seeding effects. Multivariate analysis for the in situ Raman spectra supports this complex formation pathway, and offers a new approach to monitoring multi-phase reactions during ball milling.
KW - Ball milling
KW - C-C coupling
KW - In situ
KW - Mechanochemistry
KW - Multivariate data analysis
PY - 2019
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-481872
DO - https://doi.org/10.3762/bjoc.15.110
SN - 1860-5397
VL - 15
SP - 1141
EP - 1148
PB - Beilstein Insitut
CY - Frankfurt am Main
AN - OPUS4-48187
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Linberg, Kevin
A1 - Emmerling, Franziska
A1 - Michalchuk, Adam
T1 - Unintended Rate Enhancement in Mechanochemical Kinetics by Using Poly(methyl methacrylate) Jars
JF - Crystal Growth & Design
N2 - Time-resolved in situ (TRIS) X-ray diffraction has changed how mechanochemical transformations are studied but requires the use of X-ray transparent jars often made from poly(methyl methacrylate) (PMMA). However, using PMMA jars can alter the apparent kinetics of mechanochemical polymorphism by an order of magnitude, questioning the interpretability of established TRIS methods. Our results suggest that rate enhancement in PMMA jars may not be dominated by chemical effects of the polymer, but rather a result of different equilibrium temperatures within the jar. These features must be better understood before control over mechanochemical reactions can be achieved.
KW - Mechanochemistry
KW - Organic compounds
KW - Polymers
KW - Materials
PY - 2022
UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565276
DO - https://doi.org/10.1021/acs.cgd.2c01227
SN - 1528-7483
SP - 1
EP - 5
PB - ACS Publications
AN - OPUS4-56527
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Belenguer, A
A1 - Michalchuk, Adam
A1 - Lampronti, G
A1 - Sanders, J
T1 - Using solid catalysts in disulfide-based dynamic combinatorial solution- and mechano-chemistry
JF - Chemistry Sustainable Chemistry
N2 - We here show for the first time that solid amines can act as catalysts for disulfide-based dynamic combinatorial chemistry by ball mill grinding. The mechanochemical Equilibrium for the two disulfide reactions studied is reached within one to three hours using ten different amine catalysts. This contrasts with the weeks to months to achieve solution equilibrium for most solid amine catalysts at 2%M at 2mM concentration in a suitable solvent. The final mechanochemical equilibrium is independent of the catalyst used, but varies with other ball mill grinding factors such as the presence of traces of solvent. The different efficiencies of the amines tested are discussed.
KW - Mechanochemistry
KW - Green chemistry
KW - Catalysis
PY - 2022
DO - https://doi.org/10.1002/cssc.202102416
SN - 1864-5631
VL - 15
IS - 3
SP - 1
EP - 10
PB - Wiley
AN - OPUS4-53930
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -
TY - JOUR
A1 - Kulla, Hannes
A1 - Wilke, Manuel
A1 - Fischer, Franziska
A1 - Röllig, Mathias
A1 - Maierhofer, Christiane
A1 - Emmerling, Franziska
T1 - Warming up for mechanosynthesis – temperature development in ball mills during synthesis
JF - Chemical Communications
N2 - We present a first direct measurement of the temperature during milling combined with in situ Raman spectroscopy monitoring. The data reveal a low temperature increase due to the mechanical impact and clear temperature increases as a consequence of the reaction heat. Based on the data, temperature rises as postulated in the magma plasma and hot spot theory can be excluded for soft matter milling syntheses.
KW - Thermography
KW - Milling
KW - Mechanochemistry
KW - Soft matter
PY - 2017
DO - https://doi.org/10.1039/c6cc08950j
SN - 1364-548X
SN - 1359-7345
SN - 0009-241X
VL - 53
IS - 10
SP - 1664
EP - 1667
AN - OPUS4-39251
LA - eng
AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany
ER -