TY - JOUR A1 - Chinnasamy, R. A1 - Ravi, J. A1 - Pradeep, V.V. A1 - Manoharan, D. A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Ghosh, S. T1 - Adaptable Optical Microwaveguides From Mechanically Flexible Crystalline Materials JF - Chemistry-A European Journal N2 - Flexible organic crystals (elastic and plastic) are important materials for optical waveguides, tunable optoelectronic devices, and photonic integrated circuits. Here, we present highly elastic organic crystals of a Schiff base, 1-((E)-(2,5-dichlorophenylimino)methyl)naphthalen-2-ol (1), and an azine molecule, 2,4-dibromo-6-((E)-((E)-(2,6-dichlorobenzylidene)hydrazono)methyl)phenol (2). These microcrystals are highly flexible under external mechanical force, both in the macroscopic and the microscopic regimes. The mechanical flexibility of these crystals arises as a result of weak and dispersive C−H⋅⋅⋅Cl, Cl⋅⋅⋅Cl, Br⋅⋅⋅Br, and π⋅⋅⋅π stacking interactions. Singly and doubly-bent geometries were achieved from their straight shape by a micromechanical approach using the AFM cantilever tip. Crystals of molecules 1 and 2 display a bright-green and red fluorescence (FL), respectively, and selective reabsorption of a part of their FL band. Crystals 1 and 2 exhibit optical-path-dependent low loss emissions at the termini of crystal in their straight and even in extremely bent geometries. Interestingly, the excitation position-dependent optical modes appear in both linear and bent waveguides of crystals 1 and 2, confirming their light-trapping ability. KW - Crystal growth KW - Fluorescence KW - Mechanophotonics KW - Micromanipulation KW - Optical waveguides PY - 2022 DO - https://doi.org/10.1002/chem.202200905 SN - 0947-6539 SP - 1 EP - 8 PB - Wiley VHC-Verlag AN - OPUS4-55018 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lakshmipathi, M. A1 - Dey, S. A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam T1 - Designing Dual Mechanical Response in Molecular Crystals through Cocrystallization JF - Crystal Growth and Design N2 - Two isomorphous crystals are reported based on a naphthylvinylpyridine coformer. The crystals are mechanically flexible and exhibit photosalient response to UV irradiation. We therefore show how multiple mechanical phenomena can be simultaneously designed into a single material by cocrystallization. KW - Cocrystal KW - Mechanical response PY - 2022 DO - https://doi.org/10.1021/acs.cgd.2c00913 SN - 1528-7483 VL - 22 SP - 6838 EP - 6843 PB - ACS Publ. CY - Washington, DC AN - OPUS4-56561 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ravi, J. A1 - Feiler, Torvid A1 - Mondal, A. A1 - Michalchuk, Adam A1 - Reddy, C. M. A1 - Bhattacharya, Biswajit A1 - Emmerling, Franziska A1 - Chandrasekar, R. T1 - Plastically bendable organic crystals for monolithic and hybrid micro-optical circuits JF - Advanced optical materials N2 - Fluorescent plastically bendable crystals are a promising alternative to silicon-based materials for fabricating photonic integrated circuits, owing to their optical attributes and mechanical compliance. Mechanically bendable plastic organic crystals are rare. Their formation requires anisotropic intermolecular interactions and slip planes in the crystal lattice. This work presents three fluorescent plastically bendable crystalline materials namely, 2-((E)-(6-methylpyridin-2-ylimino)methyl)-4-chlorophenol (SB1), 2-((E)-(6-methylpyridin-2-ylimino)methyl)-4-bromophenol (SB2), and 2-((E)-(6-Bromopyridin-2-ylimino)methyl)-4-bromophenol (SB3) molecules. The crystal plasticity in response to mechanical stress facilitates the fabrication of various monolithic and hybrid (with a tip-to-tip coupling) photonic circuits using mechanical micromanipulation with an atomic force microscope cantilever tip. These plastically bendable crystals act as active (self-guiding of fluorescence) and passive waveguides both in straight and extremely bent (U-, J-, and O-shaped) geometries. These microcircuits use active and passive waveguiding principles and reabsorbance and energy-transfer mechanisms for their operation, allowing input-selective and direction-specific signal transduction. KW - Flexible crystals KW - Flexible waveguide PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-565302 DO - https://doi.org/10.1002/adom.202201518 SN - 2195-1071 SP - 1 EP - 10 PB - Wiley-VCH CY - Weinheim AN - OPUS4-56530 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lakshmipathi, M. A1 - Tothadi, S. A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Ghosh, S. T1 - Different mechanical responses of dimorphic forms of Anthracene Schiffbase crystal JF - Journal of Molecular Structure N2 - We obtained concomitant dimorphic forms of Anthracene Schiffbase (N-(anthracen-9-yl methylene)-2,5- dichloroaniline) from hexane solvent. Two polymorphs can be differentiated by their morphology and mechanical properties. One form is long acicular type and elastically bendable while another form is block shaped and brittle in nature. Mechanical property is attributed to underlying crystal packing. Hirsh- feld analysis and energy framework calculations were done to corroborate structure-property correlation of two forms. KW - Elasticity KW - Mechanical properties KW - Anthracene schiff base KW - Dimorphs PY - 2021 DO - https://doi.org/10.1016/j.molstruc.2021.132182 VL - 1252 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-54356 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Halder, A. A1 - Maiti, A. A1 - Dinda, S. A1 - Bhattacharya, Biswajit A1 - Ghoshal, D. T1 - Unraveling the Role of Structural Dynamism in Metal Organic Frameworks (MOF) for Excited-State Intramolecular Proton Transfer (ESIPT) Driven Water Sensing JF - Crystal Growth & Design N2 - Ligand based modification has been performed to synthesize a pair of mixed ligands d10 MOF based materials related to a previously published compound as a base material. The previous compound was a Zn(II)-MOF, {[Zn(4-bpdh)(H2dht)](MeOH)(H2O)}n (1) [N,N′-bis(1-pyridin-4-yl-ethylidene)hydrazine = 4-bpdh and 2,5-dihydroxyterephthalic acid = H4dht], which is a five-fold interpenetrated framework and highly dynamic in nature. In the first synthetic modification, the central metal is replaced by Cd(II), which has the same framework formula as the base material, but this is a rigid compound and also there is no interpenetration in the framework. In the second modification, along with the metal center, the 4,4′- coordinating N,N′-donor ligand is replaced by an isomeric 3,3′-coordinating N,N′- donor linker. In this compound, the dynamism is regenerated. The dynamic nature can be realized by the extensive PXRD studies and characteristic “step-shaped” gas/solvent adsorption behavior for CO2, water, and ethanol. Furthermore, all these 3D MOFs show excited-state intramolecular proton transfer phenomena and water sensing properties in different organic solvents. Here excitingly, the ease of water sensing property is directly related to the dynamic behavior of the framework which has been studied thoroughly in terms of structural correlation. KW - MOFs PY - 2021 DO - https://doi.org/10.1021/acs.cgd.1c00446 SN - 1528-7483 VL - 21 IS - 11 SP - 6110 EP - 6118 PB - ACS Publications AN - OPUS4-53903 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Feiler, Torvid A1 - Michalchuk, Adam A1 - Schröder, V. A1 - List-Kratochvil, E. A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit T1 - Elastic Flexibility in an Optically Active Naphthalidenimine-Based Single Crystal JF - Crystals N2 - Organic single crystals that combine mechanical flexibility and optical properties are important for developing flexible optical devices, but examples of such crystals remain scarce. Both mechanical flexibility and optical activity depend on the underlying crystal packing and the nature of the intermolecular interactions present in the solid state. Hence, both properties can be expected to be tunable by small chemical modifications to the organic molecule. By incorporating a chlorine atom, a reportedly mechanically flexible crystal of (E)-1-(4-bromo-phenyl)iminomethyl-2-hydroxylnaphthalene (BPIN) produces (E)-1-(4-bromo-2-chloro-phenyl)iminomethyl-2-hydroxyl-naphthalene (BCPIN). BCPIN crystals show elastic bending similar to BPIN upon mechanical stress, but exhibit a remarkable difference in their optical properties as a result of the chemical modification to the backbone of the organic molecule. This work thus demonstrates that the optical properties and mechanical flexibility of molecular materials can, in principle, be tuned independently. KW - Elastic Crystal PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-539040 DO - https://doi.org/10.3390/cryst11111397 VL - 11 IS - 11 SP - 1397 PB - MDPI AN - OPUS4-53904 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Feiler, Torvid A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam A1 - Rhim, S.-Y. A1 - Schröder, V. A1 - List-Kratochvil, E. A1 - Emmerling, Franziska T1 - Mechanically flexible crystals: materials for new generation of responsive materials N2 - Based on the nature of the deformation, molecular crystals can be defined as being plastically (irreversible) or elastically (reversible)bendable. The mechanical response of crystals is thereby directly related to they structure.The structural elements required for a specific mechanical behavior are known, so that compounds with these properties can be synthesized by applying the rules of crystal engineering. T2 - Berlin Science Week CY - Berlin, Germany DA - 01.11.2021 KW - Flexible crystals PY - 2021 AN - OPUS4-53907 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Liu, X. A1 - Michalchuk, Adam A1 - Bhattacharya, Biswajit A1 - Emmerling, Franziska A1 - Pulham, C. T1 - High-pressure reversibility in a plastically flexible coordination polymer crystal JF - Nature Communications N2 - Single crystals which exhibit mechanical flexibility are promising materials for advanced technological applications. Before such materials can be used, a detailed understanding of the mechanisms of bending is needed. Using single crystal X-ray diffraction and microfocus Raman spectroscopy, we study in atomic detail the high-pressure response of the plastically flexible coordination polymer [Zn(μ-Cl)2(3,5-dichloropyridine)2]n (1). Contradictory to three-point bending, quasi-hydrostatic compression of (1) is completely reversible, even following compression to over 9 GPa. A structural phase transition is observed at ca. 5 GPa. DFT calculations show this transition to result from the pressure-induced softening of low-frequency vibrations. This phase transition is not observed during three-point-bending. Microfocus synchrotron X-ray diffraction revealed that bending yields significant mosaicity, as opposed to compression. Hence, our studies indicate of overall disparate mechanical responses of bulk flexibility and quasi-hydrostatic compression within the same crystal lattice. We suspect this to be a general feature of plastically bendable materials. KW - High pressure KW - Density functional theory KW - Mechanically flexible crystals PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530360 DO - https://doi.org/10.1038/s41467-021-24165-x VL - 12 IS - 1 SP - 3871 AN - OPUS4-53036 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 - 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 - Lakshmipathi, M. A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Ghosh, S. T1 - Structure-mechanical property correlation of a series of 4-(1-Napthylvinyl) pyridine based cocrystals JF - Journal of molecular structure N2 - We obtained three 4-(1-Napthylvinyl) pyridine based cocrystals ( 1–3 ) and studied its structure mechan- ical property correlation which aimed towards various applications for photo switches, mechanical ac- tuators etc. Selection of coformer molecules is important in fine tuning mechanical property outcome of synthesized cocrystals. Amongst three cocrystals, cocrystal 1 is mechanically flexible and its mechani- cal property is attributed to underlying crystal packing features which is in line with existing elastically bendable crystals while other two cocrystals ( 2, 3 ) are brittle in nature. Hirshfeld analysis was carried out to illustrate structure-property correlation particularly in terms of number as well as types of non- covalent interactions in the lattice and further to corroborate the space of the molecules in the lattice. KW - Cocrystals KW - Mechanical properties KW - Halogen bond interaction KW - Structure-mechanical property correlation PY - 2022 DO - https://doi.org/10.1016/j.molstruc.2022.133670 SN - 0022-2860 VL - 1268 SP - 1 EP - 16 PB - Elsevier CY - Amsterdam AN - OPUS4-55547 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Thekkeppat, N. P. A1 - Bhattacharya, Biswajit A1 - Tothadi, S. A1 - Ghosh, S. T1 - Mechanically flexible crystals of styryl quinoline derivatives JF - Journal of Molecular Structure N2 - Herein, we report three crystals of styryl quinoline derivatives. All these three crystals are mechanically flexible crystals, isostructural and also all of them comply with the common underlying features for elas- tic flexibility like absence of slip plane, criss-cross packing arrangement of neighbouring tapes, presence of weak and dispersive interactions such as halogen bonds, hydrogen bonds etc. The interactions facilitate easy movement of molecules under application of pressure thereby imparting elasticity. Further, the crys- tals were found to be blue light emitting making them promising candidates for optical waveguides. The optical properties were combined with flexibility by using crystal engineering approach towards achiev- ing various applications such as flexible OLEDs, optical waveguides, flexible optoelectronics etc. KW - Mechanical flexibility KW - Halogen bond KW - Fluorescence PY - 2022 DO - https://doi.org/10.1016/j.molstruc.2022.133293 SN - 0022-2860 VL - 1265 SP - 1 EP - 7 PB - Elsevier CY - Amsterdam AN - OPUS4-55549 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 - Pakrashy, S. A1 - Mandal, P. K. A1 - Goswami, J. N. A1 - Dey, S. K. A1 - Choudhury, S. M. A1 - Bhattacharya, Biswajit A1 - Emmerling, Franziska A1 - Alasmary, F. A. A1 - Dolai, M. T1 - Bioinformatics and Network Pharmacology of the First Crystal Structured Clerodin: Anticancer and Antioxidant Potential against Human Breast Carcinoma Cell JF - ACS Omega N2 - Clerodin was isolated from the medicinal plant Clerodendrum infortunatum, and CSD search showed the first crystal structure of clerodin by a single-crystal X-ray diffraction study. We checked its binding potential with target proteins by docking and conducted network pharmacology analysis, ADMET analysis, in silico pathway analysis, normal mode analysis (NMA), and cytotoxic activity studies to evaluate clerodin as a potential anticancer agent. The cell viability studies of clerodin on the human breast carcinoma cell line (MCF-7) showed toxicity on MCF-7 cells but no toxicity toward normal human lymphocyte cells (HLCs). The anticancer mechanism of clerodin was validated by its enhanced capacity to produce intracellular reactive oxygen species (ROS) and to lower the reduced glutathione content in MCF-7 cells. KW - Anticancer KW - Clerodin PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-567600 DO - https://doi.org/10.1021/acsomega.2c07173 SN - 2470-1343 VL - 7 IS - 51 SP - 48572 EP - 48582 PB - ACS Publ. CY - Washington, DC AN - OPUS4-56760 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 - Feiler, Torvid A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam A1 - Schröder, V. A1 - List-Kratochvil, E. A1 - Emmerling, Franziska T1 - Mechanochemical Syntheses of Isostructural Luminescent Cocrystals of 9-Anthracenecarboxylic Acid with two Dipyridines Coformers JF - Crystals N2 - Tuning and controlling the solid-state photophysical properties of organic luminophore are very important to develop next-generation organic luminescent materials. With the aim of discovering new functional luminescent materials, new cocrystals of 9-anthracene carboxylic acid (ACA) were prepared with two different dipyridine coformers: 1,2-bis(4-pyridyl)ethylene and 1,2-bis(4-pyridyl)ethane. The cocrystals were successfully obtained by both mechanochemical approaches and conventional solvent crystallization. The newly obtained crystalline solids were characterized thoroughly using a combination of single crystal X-ray diffraction, powder X-ray diffraction, Fourier-transform infrared spectroscopy, differential thermal analysis, and thermogravimetric analysis. Structural analysis revealed that the cocrystals are isostructural, exhibiting two-fold interpenetrated hydrogen bonded networks. While the O–H···N hydrogen bonds adopts a primary role in the stabilization of the cocrystal phases, the C–H···O hydrogen bonding interactions appear to play a significant role in guiding the three-dimensional assembly. Both π···π and C–H···π interactions assist in stabilizing the interpenetrated structure. The photoluminescence properties of both the starting materials and cocrystals were examined in their solid states. All the cocrystals display tunable photophysical properties as compared to pure ACA. Density functional theory simulations suggest that the modified optical properties result from charge transfers between the ACA and coformer molecules in each case. This study demonstrates the potential of crystal engineering to design solid-state luminescence switching materials through cocrystallization. KW - Cocrystal KW - Mechanochemical synthesis KW - Luminescence KW - X-ray diffraction KW - DFT calculation PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-518226 DO - https://doi.org/10.3390/cryst10100889 VL - 10 IS - 10 SP - 889 PB - MDPI AN - OPUS4-51822 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kumari, N. A1 - Bhattacharya, Biswajit A1 - Roy, P. A1 - Michalchuk, Adam A1 - Ghosh, A. A1 - Emmerling, Franziska T1 - Enhancing the Pharmaceutical Properties of Pirfenidone by Mechanochemical Cocrystallization JF - Crystal Growth and Design N2 - Pirfenidone is an important drug molecule used in the treatment of idiopathic lung fibrosis. Although approved by the USFDA in 2014, pirfenidone’s aqueous solubility is too high and must be mitigated by additives. In this work, the cocrystallization of pirfenidone is explored as an alternative approach to reducing its solubility. Herein, an anhydrous form of pirfenidone is reported, alongside its first two reported cocrystals. The new crystalline solids are thoroughly characterized by single crystal X-ray diffraction (SCXRD), powder X-ray diffraction analysis (PXRD), Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Equilibrium solubility and intrinsic dissolution rates (IDR) are studied for the cocrystals and compared to that of the parent drug. Both cocrystal forms exhibit drastically lower aqueous solubility (by up to 90%) and dissolution rates, rationalized based on both lattice energy calculations and consideration of intermolecular interactions in the solid state. Furthermore, we compare the physicochemical properties of solution-based material with that of material produced mechanochemically. Importantly, no differences are observed between the two production methods. This work demonstrates the strength of crystal Engineering strategies to beneficially modify important pharmaceutical properties and highlights the potential of mechanochemistry to facilitate this in an environmentally benign way. KW - Mechanochemistry PY - 2019 DO - https://doi.org/10.1021/acs.cgd.9b00932 VL - 19 IS - 11 SP - 6482 EP - 6492 PB - ACS Publications AN - OPUS4-49828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bhattacharya, Biswajit A1 - Das, S. A1 - Lal, G. A1 - Soni, S. R. A1 - Ghosh, A. A1 - Reddy, C. M. A1 - Ghosh, S. T1 - Screening, crystal structures and solubility studies of a series of multidrug salt hydrates and cocrystals of fenamic acids with trimethoprim and sulfamethazine JF - Journal of Molecular Structure N2 - Multidrug solids have a potential use to efficiently treat and control a superfluity of medical conditions. To address the current drawbacks of drug development in R&D, it was targeted to achieve new pharmaceutical solid forms of fenamic acids having improved solubility and thermal stability. Subsequently, five new multicomponent solids consisting of three salt hydrates of trimethoprim (TMP) with mefenamic acid (TMP-MFA-H2O), tolfenamic acid (TMP-TFA-H2O) and flufenamic acid (TMP-FFA-H2O), and two cocrystals of sulfamethazine (SFZ) with flufenamic acid (SFZ-FFA) and niflumic acid (SFZ-NFA) were prepared by liquid assisted grinding. Looking at the structures of active pharmaceutical ingredient (API) molecules, it was quite expected that a wide range of supramolecular synthons would lead to cocrystallization. New forms were characterized thoroughly by various solid-state techniques, including single crystal X-ray diffraction (SCXRD), which provided details of hydrogen bonding, molecular packing and interactions between drug and coformer. Kinetic solubility at pH 7.4 buffer study has been carried out and a comparison is made with respect to the parent drugs. A significant enhancement of NSAIDs solubility was observed in all salt hydrate systems of TMP. Thus with increasing physicochemical properties such as improved solubility further leads to the enhancement of bioavailability, which has implications to overcoming the formulation related problems of active pharmaceutical ingredients (APIs). KW - Cocrystals KW - Crystal engineering KW - Solubility PY - 2020 DO - https://doi.org/10.1016/j.molstruc.2019.127028 SN - 0022-2860 VL - 1199 SP - 127028 PB - Elsevier B.V. AN - OPUS4-49873 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam A1 - Emmerling, Franziska T1 - Revealing Mechanical Plastic Bending in Coordination Polymer Crystals N2 - Crystalline molecular materials with mechanical flexibility are promising for technological development. This is particularly true for the development of advanced materials with optoelectronic and biomedical applications. While a growing number of mechanically flexible crystalline molecular materials are being reported,1 they remain scarce. At present, most discoveries are serendipitous, as limited design strategies are currently known. Amongst these strategies Desiraju et. al. suggested that elastic materials must contain herringbone structures.2 For plastic crystals, the so-called ‘shape-synthon’ strategy has been developed, in which weak non-covalent interactions are introduced into structures to facilitate mobility of molecules.3 This includes formation of slip planes. Generally, these models have performed very well at predicting and rationalizing the mechanical properties of new materials. Recently, however, a family of one-dimensional covalent networks (coordination polymers; CPs) has been described, which show mechanical elasticity. With drastically different structural chemistry, these systems do not seem to adhere to the currently established rules. Herein, we present the first such system: a plastically bendable crystal of a 1D CP, [Zn(-Cl)2(3,5-Cl2Py)2]n (where 3,5-Cl2Py = 3,5-dichloro pyridine). This CP crystallizes in a tetragonal, and can therefore be bent over two major faces to acute angles without fracturing. We conducted bending and indentation experiments to quantify the mechanical properties of the CP crystal. This was complimented by Vibrational (Raman and Terahertz) spectroscopy and theoretical calculations for deeper understanding of molecular level structural deformation. T2 - 32nd European Crystallographic Meeting (ECM32) CY - University of Vienna, Vienna, Austria DA - 18.08.2019 KW - Mechanical Flexiblity KW - Crystal engineering KW - Coordination Polymers PY - 2019 AN - OPUS4-49875 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manoharan, Deepak A1 - Ahmad, Shamim A1 - Tothadi, Srinu A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Ghosh, Soumyajit T1 - Linker size dependent mechanical properties of di-imine based molecular crystals JF - CrystEngComm N2 - We have demonstrated the ability to modify the mechanical flexibility of molecular crystals by modulating the length of intervening linker moieties while keeping the terminal shape synthons the same. KW - Mechanically flexible molecular crystals KW - Mechanical properties KW - Crystal Engineering PY - 2023 DO - https://doi.org/10.1039/D3CE00928A SN - 1466-8033 SP - 1 EP - 8 PB - RSC CY - London AN - OPUS4-58836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bhattacharya, Biswajit A1 - Akhmetova, Irina A1 - Rautenberg, Max A1 - Emmerling, Franziska T1 - Mechanochemical synthesis of phosphonate-based proton conducting metal organic frameworks and hydrogen-bonded metal phosphonates N2 - Proton exchange membrane fuel cells (PEMFCs) are one of the most promising alternative green energy technologies that deliver high energy density without CO2 emissions. The proton conductivity of proton exchange membranes (PEM) contributes to the overall efficiency of a PEMFC. Materials being used as PEMs must exhibit high proton conductivity at the working conditions of the targeted PEMFC. To date, Nafion and Nafion-like polymers with acidic functionality are widely used as membrane materials due to their high proton conductivity in the range of 10-1 to 10-2 Scm-1 at higher relative humidity. However, these materials suffer from high costs, hazardous production process, and poor performance at high temperatures, limiting their versatility. In this context, 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 challenging bulk synthesis for real-world applications of these materials. Herein, we present mechanochemical gram-scale synthesis of series of mixed ligand metal organic frameworks (MOFs) and metal hydrogen‐bonded organic frameworks (MHOFs) using phenylene diphosphonic acid and 1-hydroxyethylidene-1,1-diphosphonic acid with different bipyridyl type of ligands, respectively. In all cases, the existence of extensive hydrogen bonds with amphiprotic uncoordinated phosphonate hydroxyl and oxygen atoms, the frameworks exhibited high proton conductivity. The study demonstrates the potential of green mechanosynthesis for preparations of framework-based proton conducting materials in bulk scale for green energy generation. T2 - 4th International Conference on Phosphonate Chemistry, Science and Technology, ICOPHOS-4 CY - Crete, Greece DA - 02.10.2023 KW - Proton exchange membrane fuel cells KW - Metal organic frameworks KW - Proton conducting materials PY - 2023 AN - OPUS4-58837 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manoharan, D. A1 - Megha, S. N. A1 - Kiran, M. S. R. N. A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Ghosh, S. T1 - Designing the Mechanical Plasticity of Benzylidene Indanones Based Molecular Crystals by Crystal Engineering JF - Crystal Growth & Design N2 - Mechanically flexible molecular crystals have important implications in flexible optoelectronics, optical waveguides, etc. We report a series of 2-benzylidene 1-indanone based plastic crystals. Moreover, we have shown how plasticity can be fine-tuned through controlling intermolecular interactions. KW - Mechanical flexibility KW - Organic crystal KW - Mechanical property PY - 2023 DO - https://doi.org/10.1021/acs.cgd.2c01137 SN - 1528-7483 VL - 23 SP - 657 EP - 661 PB - ACS Publications AN - OPUS4-57773 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 - Karafiludis, Stephanos A1 - Bhattacharya, Biswajit A1 - de Oliveira Guilherme Buzanich, Ana A1 - Fink, Friedrich A1 - Feldmann, Ines A1 - ten Elshof, J. E. A1 - Emmerling, Franziska A1 - Stawski, Tomasz T1 - Thermally processed Ni-and Co-struvites as functional materials for proton conductivity JF - Dalton Transactions N2 - We present how mesoporosity can be engineered in transition metal phosphate (TMPs) materials in a template-free manner. The method involves the transformation of a precursor metal phosphate phase, called M-struvite (NH4MPO4·6H2O, M = Mg2+, Ni2+, Co2+, NixCo1−x2+). It relies on the thermal decomposition of crystalline M-struvite precursors to an amorphous and simultaneously mesoporous phase, which forms during degassing of NH3 and H2O. The temporal evolution of mesoporous frameworks and the response of the metal coordination environment were followed by in situ and ex situ scattering and diffraction, as well as X-ray spectroscopy. Despite sharing the same precursor struvite structure, different amorphous and mesoporous structures were obtained depending on the involved transition metal. We highlight the systematic differences in absolute surface area, pore shape, pore size, and phase transitions depending on the metal cation present in the analogous M-struvites. The amorphous structures of thermally decomposed Mg-, Ni- and NixCo1−x-struvites exhibit high surface areas and pore volumes (240 m2 g−1 and 0.32 cm−3 g−1 for Mg and 90 m2 g−1 and 0.13 cm−3 g−1 for Ni). We propose that the low-cost, environmentally friendly M-struvites could be obtained as recycling products from industrial and agricultural wastewaters. These waste products could be then upcycled into mesoporous TMPs through a simple thermal treatment for further application, for instance in (electro)catalysis. KW - Struvite KW - Phosphates KW - Transition metals KW - Proton conductivity PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-575862 DO - https://doi.org/10.1039/D3DT00839H SN - 1477-9226 SP - 1 EP - 13 PB - Royal Society of Chemisty (RSC) CY - London/Cambridge AN - OPUS4-57586 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manoharan, D. A1 - Ahmad, S. A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Ghosh, S. T1 - Stress and light sensitive dual-mechanical property of acylhydrazone crystal JF - CrystEngComm N2 - Mechanically dual-responsive molecular crystals have gained ubstantial interest among researchers due to their significant applications in various fields. However, incorporation of disparate mechanical responses in the same crystalline material is still a challenging issue and is continuously being explored. Here, we report long acicular crystals derived from 4-bromobenzhydrazide and 9-anthraldehyde exhibit both stressinduced mechanical bending and blue-light induced photomechanical bending. Furthermore, the crystals show thermal back isomerization upon gradual heating. These two distinct mechanical responses in the crystalline phase have been studied and their structure–property correlation have been established. KW - Light sensitive crystal KW - Mechanical flexibility KW - Organic crystal PY - 2023 DO - https://doi.org/10.1039/d3ce00296a VL - 25 IS - 21 SP - 3237 EP - 3244 PB - Royal Society of Chemisty (RSC) CY - London/Cambridge AN - OPUS4-57593 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Manoharan, Deepak A1 - Ranjan, Subham A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit A1 - Takamizawa, Satoshi A1 - Ghosh, Soumyajit T1 - Elasto-plastic behaviour with reversible thermosalient expansion in acrylonitrile-based organic crystals JF - Journal of Materials Chemistry C N2 - Crystalline materials that exhibit reversible mechanical responses upon exposure to external stimuli have garnered significant attention owing to their potential applications in various fields. Herein, we report a crystal of (2Z,2′Z)-2,2′-(1,4-phenylene)bis(3-(4-bromophenyl)acrylonitrile) (DSBr), which displays simultaneous elasto-plastic behaviour and reversible thermosalient effects. While elasto-plastic behaviour is attributed to underlying packing features, reversible thermosalient expansion is attributed to uniaxial expansion mediated by heat. Exceptional length increase and contraction upon cooling is due to the restorative nature of weak interactions through a cooperative effect. The cooperative movement of molecules is reflected in the unidirectional expansion of the habit plane. Thermosalient reversible expansion–contraction in elasto-plastic crystals have not been discussed in the literature so far. Detailed analysis reported herein provides a comprehensive understanding of the underlying mechanism of flexibility and thermosalient responses. This crystal's unique blend of reversible thermal expansion with flexibility holds substantial promise for applications in flexible thermal actuators. KW - Materials Chemistry KW - General Chemistry PY - 2024 DO - https://doi.org/10.1039/D3TC04272C SN - 2050-7526 SP - 1 EP - 11 PB - Royal Society of Chemistry (RSC) AN - OPUS4-59527 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Goswami, Juli Nanda A1 - Haque, Najirul A1 - Seikh, Asiful H. A1 - Bhattacharya, Biswajit A1 - Emmerling, Franziska A1 - Bar, Nimai A1 - Ifseisi, Ahmad A. A1 - Biswas, Surajit A1 - Dolai, Malay T1 - Carboxylative cyclization of propargyl alcohols with carbon dioxide for the synthesis of α-alkylidene cyclic carbonates in presence of Co(III) schiff base complex catalyst JF - Journal of Molecular Structure N2 - A cobalt(III) complex, [Co(L)3](DMF) (1) of Schiff base ligand HL, 2-((E)-(benzylimino)methyl)-4-bromophenol is prepared and single crystal X-ray structural analysis have also been performed. The structures of complex 1 showed hexa-coordinated mononuclear systems that adopt octahedral geometry. The complex has also exhibited the supramolecular networks through non-covalent interactions like H-bonding, C–Hπ stacking. Moreover, the complex 1 is very effective in the catalytic fixation of carbon dioxide in propergyl alcohols to produce α-alkylidene cyclic carbonates. The catalytic production of α-alkylidene cyclic carbonates have been carried out through carboxylative cyclization of propargyl alcohols using CO2 balloon of 1 atm pressure at 80 ◦C. Solvent free condition (green synthesis) made this catalytic protocol eco-friendly towards the environment. Utilizing various substrates of propargyl alcohols moderate to high percentage yield (62–95%) of respective α-alkylidene cyclic carbonates product have been isolated over this catalytic reaction. Besides, the theoretical calculations (DFT) was performed for the prediction of probable mechanism of the catalytic reaction KW - Catalytic fixation of carbon dioxide KW - Carboxylative cyclization of propargyl alcohols KW - Cobalt (III) Schiff base complex KW - X-ray crystal analysis PY - 2024 DO - https://doi.org/10.1016/j.molstruc.2023.136868 SN - 0022-2860 VL - 1296 IS - Part 1 SP - 1 EP - 8 PB - Elsevier B.V. AN - OPUS4-58947 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Feiler, Torvid A1 - Yasuda, N. A1 - Michalchuk, Adam A1 - Emmerling, Franziska A1 - Bhattacharya, Biswajit T1 - Mechanistic Investigation of an Elastically Flexible Organic Crystal JF - Crystal Growth & Design N2 - Mechanical flexibility in molecular crystals is a fascinating behavior with potential for developing advanced technologies. However, the phenomenon of mechanical bending is poorly understood. We explore for the first time the atomistic origin of elastic bending in a single component organic crystal using a combination of μ-focus synchrotron X-ray diffraction and ab initio simulation. KW - Flexible crystals KW - DFT calculation KW - Bending mechanism PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581949 DO - https://doi.org/10.1021/acs.cgd.3c00473 SN - 1528-7483 VL - 23 IS - 9 SP - 6244 EP - 6249 PB - ACS Publications AN - OPUS4-58194 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Nag, Sayak A1 - Emmerling, Franziska A1 - Tothadi, Srinu A1 - Bhattacharya, Biswajit A1 - Ghosh, Soumyajit T1 - Distinct photomechanical responses of two new 1,3-dimethylbarbituric acid derivative crystals JF - CrystEngComm N2 - We demonstrate two distinct photomechanical responses (i.e. photomechanical bending and photosalient bursting) of two new 1,3-dimethylbarbituric acid derivative crystals based on tailoring their substituents and the modulation of their spacers. KW - Crystal engineering KW - Fexible crystals PY - 2024 DO - https://doi.org/10.1039/D4CE00233D SP - 1 EP - 12 PB - Royal Society of Chemistry (RSC) AN - OPUS4-60141 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam A1 - Silbernagl, Dorothee A1 - Rautenberg, Max A1 - Schmid, Thomas A1 - Feiler, Torvid A1 - Reimann, K. A1 - Ghalgaoui, A. A1 - Sturm, Heinz A1 - Paulus, B. A1 - Emmerling, Franziska T1 - A Mechanistic Perspective on Plastically Flexible Coordination Polymers JF - Angewandte Chemie N2 - Mechanical flexibility in single crystals of covalently bound materials is a fascinating and poorly understood phenomenon. We present here the first example of a plastically flexible one-dimensional (1D) coordination polymer. The compound [Zn(m-Cl)2(3,5-dichloropyridine)2]n is flexible over two crystallographic faces. Remarkably, the single crystal remains intact when bent to 1808. A combination of microscopy, diffraction, and spectroscopic studies have been used to probe the structural response of the crystal lattice to mechanical bending. Deformation of the covalent polymer chains does not appear to be responsible for the observed macroscopic bending. Instead, our results suggest that mechanical bending occurs by displacement of the coordination polymer chains. Based on experimental and theoretical evidence, we propose a new model for mechanical flexibility in 1D coordination polymers. Moreover, our calculations propose a cause of the different mechanical properties of this compound and a structurally similar elastic material KW - Coordination polymer KW - Flexible crystals KW - Mechanical properties KW - Plastic deformation PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-504755 DO - https://doi.org/10.1002/anie.201914798 VL - 59 IS - 14 SP - 5557 EP - 5561 PB - Wiley-VCH AN - OPUS4-50475 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bhattacharya, Biswajit A1 - Michalchuk, Adam A. L. A1 - Silbernagl, Dorothee A1 - Yasuda, N. A1 - Feiler, Torvid A1 - Sturm, Heinz A1 - Emmerling, Franziska T1 - An atomistic mechanism for elasto-plastic bending in molecular crystals JF - Chemical Science N2 - Mechanically flexible single crystals of molecular materials offer potential for a multitude of new directions in advanced materials design. Before the full potential of such materials can be exploited, insight into their mechanisms of action must be better understood. Such insight can be only obtained through synergistic use of advanced experimentation and simulation. We herein report the first detailed mechanistic study of elasto-plastic flexibility in a molecular solid. An atomistic origin for this mechanical behaviour is proposed through a combination of atomic force microscopy, μ-focus synchrotron X-ray diffraction, Raman spectroscopy, ab initio simulation, and computed elastic tensors. Our findings suggest that elastic and plastic bending are intimately linked and result from extensions of the same molecular deformations. The proposed mechanism bridges the gap between contested mechanisms, suggesting its applicability as a general mechanism for elastic and plastic bending in organic molecular crystals. KW - Mechanical property KW - Mechanical flexibility KW - Organic crystal PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-577722 DO - https://doi.org/10.1039/D2SC06470G SN - 2041-6520 VL - 14 IS - 13 SP - 3441 EP - 3450 PB - Royal Society of Chemisty (RSC) CY - London/Cambridge AN - OPUS4-57772 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -