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
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 - 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
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 - 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
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 - 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
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 - 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
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 - 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?
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 - 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
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 - 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
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 -
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
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 - Wilke, Manuel
A1 - Akhemtova, Irina
A1 - Rademann, K.
A1 - Emmerling, Franziska
T1 - Mechanochemical synthesis of cerium(IV)-phosphonates
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 - 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
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 - Haferkamp, Sebastian
A1 - Fischer, Franziska
A1 - Kraus, Werner
A1 - Emmerling, Franziska
T1 - Mechanochemical Knoevenagel condensation investigated in situ
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 - 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
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 - 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
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 - 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
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 - 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
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 - 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
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 - Tumanov, I.
A1 - Tumanov, E.
A1 - Michalchuk, Adam
T1 - Ball size or ball mass – what matters in organic mechanochemical synthesis?
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 - 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
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 - 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
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 -