Acta crystallographica Section B, Structural science, crystal engineering and materials最新文献

{"title":"Polymorph sampling with coupling to extended variables: enhanced sampling of polymorph energy landscapes and free energy perturbation of polymorph ensembles.","authors":"Eric J Chan, Mark E Tuckerman","doi":"10.1107/S205252062400132X","DOIUrl":"10.1107/S205252062400132X","url":null,"abstract":"<p><p>A novel approach to computationally enhance the sampling of molecular crystal structures is proposed and tested. This method is based on the use of extended variables coupled to a Monte Carlo based crystal polymorph generator. Inspired by the established technique of quasi-random sampling of polymorphs using the rigid molecule constraint, this approach represents molecular clusters as extended variables within a thermal reservoir. Polymorph unit-cell variables are generated using pseudo-random sampling. Within this framework, a harmonic coupling between the extended variables and polymorph configurations is established. The extended variables remain fixed during the inner loop dedicated to polymorph sampling, enforcing a stepwise propagation of the extended variables to maintain system exploration. The final processing step results in a polymorph energy landscape, where the raw structures sampled to create the extended variable trajectory are re-optimized without the thermal coupling term. The foundational principles of this approach are described and its effectiveness using both a Metropolis Monte Carlo type algorithm and modifications that incorporate replica exchange is demonstrated. A comparison is provided with pseudo-random sampling of polymorphs for the molecule coumarin. The choice to test a design of this algorithm as relevant for enhanced sampling of crystal structures was due to the obvious relation between molecular structure variables and corresponding crystal polymorphs as representative of the inherent vapor to crystal transitions that exist in nature. Additionally, it is shown that the trajectories of extended variables can be harnessed to extract fluctuation properties that can lead to valuable insights. A novel thermodynamic variable is introduced: the free energy difference between ensembles of Z' = 1 and Z' = 2 crystal polymorphs.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11789163/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142455731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The seventh blind test of crystal structure prediction: structure ranking methods.","authors":"Lily M Hunnisett, Nicholas Francia, Jonas Nyman, Nathan S Abraham, Srinivasulu Aitipamula, Tamador Alkhidir, Mubarak Almehairbi, Andrea Anelli, Dylan M Anstine, John E Anthony, Joseph E Arnold, Faezeh Bahrami, Michael A Bellucci, Gregory J O Beran, Rajni M Bhardwaj, Raffaello Bianco, Joanna A Bis, A Daniel Boese, James Bramley, Doris E Braun, Patrick W V Butler, Joseph Cadden, Stephen Carino, Ctirad Červinka, Eric J Chan, Chao Chang, Sarah M Clarke, Simon J Coles, Cameron J Cook, Richard I Cooper, Tom Darden, Graeme M Day, Wenda Deng, Hanno Dietrich, Antonio DiPasquale, Bhausaheb Dhokale, Bouke P van Eijck, Mark R J Elsegood, Dzmitry Firaha, Wenbo Fu, Kaori Fukuzawa, Nikolaos Galanakis, Hitoshi Goto, Chandler Greenwell, Rui Guo, Jürgen Harter, Julian Helfferich, Johannes Hoja, John Hone, Richard Hong, Michal Hušák, Yasuhiro Ikabata, Olexandr Isayev, Ommair Ishaque, Varsha Jain, Yingdi Jin, Aling Jing, Erin R Johnson, Ian Jones, K V Jovan Jose, Elena A Kabova, Adam Keates, Paul F Kelly, Jiří Klimeš, Veronika Kostková, He Li, Xiaolu Lin, Alexander List, Congcong Liu, Yifei Michelle Liu, Zenghui Liu, Ivor Lončarić, Joseph W Lubach, Jan Ludík, Alexander A Maryewski, Noa Marom, Hiroyuki Matsui, Alessandra Mattei, R Alex Mayo, John W Melkumov, Bruno Mladineo, Sharmarke Mohamed, Zahrasadat Momenzadeh Abardeh, Hari S Muddana, Naofumi Nakayama, Kamal Singh Nayal, Marcus A Neumann, Rahul Nikhar, Shigeaki Obata, Dana O'Connor, Artem R Oganov, Koji Okuwaki, Alberto Otero-de-la-Roza, Sean Parkin, Antonio Parunov, Rafał Podeszwa, Alastair J A Price, Louise S Price, Sarah L Price, Michael R Probert, Angeles Pulido, Gunjan Rajendra Ramteke, Atta Ur Rehman, Susan M Reutzel-Edens, Jutta Rogal, Marta J Ross, Adrian F Rumson, Ghazala Sadiq, Zeinab M Saeed, Alireza Salimi, Kiran Sasikumar, Sivakumar Sekharan, Kenneth Shankland, Baimei Shi, Xuekun Shi, Kotaro Shinohara, A Geoffrey Skillman, Hongxing Song, Nina Strasser, Jacco van de Streek, Isaac J Sugden, Guangxu Sun, Krzysztof Szalewicz, Lu Tan, Kehan Tang, Frank Tarczynski, Christopher R Taylor, Alexandre Tkatchenko, Petr Touš, Mark E Tuckerman, Pablo A Unzueta, Yohei Utsumi, Leslie Vogt-Maranto, Jake Weatherston, Luke J Wilkinson, Robert D Willacy, Lukasz Wojtas, Grahame R Woollam, Yi Yang, Zhuocen Yang, Etsuo Yonemochi, Xin Yue, Qun Zeng, Tian Zhou, Yunfei Zhou, Roman Zubatyuk, Jason C Cole","doi":"10.1107/S2052520624008679","DOIUrl":"10.1107/S2052520624008679","url":null,"abstract":"<p><p>A seventh blind test of crystal structure prediction has been organized by the Cambridge Crystallographic Data Centre. The results are presented in two parts, with this second part focusing on methods for ranking crystal structures in order of stability. The exercise involved standardized sets of structures seeded from a range of structure generation methods. Participants from 22 groups applied several periodic DFT-D methods, machine learned potentials, force fields derived from empirical data or quantum chemical calculations, and various combinations of the above. In addition, one non-energy-based scoring function was used. Results showed that periodic DFT-D methods overall agreed with experimental data within expected error margins, while one machine learned model, applying system-specific AIMnet potentials, agreed with experiment in many cases demonstrating promise as an efficient alternative to DFT-based methods. For target XXXII, a consensus was reached across periodic DFT methods, with consistently high predicted energies of experimental forms relative to the global minimum (above 4 kJ mol^-1 at both low and ambient temperatures) suggesting a more stable polymorph is likely not yet observed. The calculation of free energies at ambient temperatures offered improvement of predictions only in some cases (for targets XXVII and XXXI). Several avenues for future research have been suggested, highlighting the need for greater efficiency considering the vast amounts of resources utilized in many cases.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11789160/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142455734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Symmetry, magnetic transitions and multiferroic properties of B-site-ordered A₂MnB'O₆ perovskites (B' = [Co, Ni]).","authors":"Jose Luis Garcia-Muñoz, Xiaodong Zhang, Gloria Subías, Javier Blasco","doi":"10.1107/S2052520624009454","DOIUrl":"10.1107/S2052520624009454","url":null,"abstract":"<p><p>The presence of magnetic atoms at the A and B sites and the coupling between these two spin subsystems in perovskites gives rise to a variety of exciting effects. In particular this coupling attracts interest from the field of novel multiferroic and magnetoelectric oxides. Moreover, magnetic double perovskites presenting cationic order at the B sites incorporate an additional modulation that can favor symmetry breaking, multiferroic, magnetoelectric and polar phases. Here, we describe the magnetic structures obtained from neutron diffraction and analyze the symmetry properties of well ordered A₂MnB'O₆ double perovskites with A = Lu, Yb, Tm, Er, Ho, Y, Tb, La_0.5Tb_0.5, La and B' = Co or Ni. A rich variety of magnetic orders is formed that have been identified and described, and their symmetry properties are discussed in relation to the multiferroic and magnetoelectric properties of the different compounds.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11789168/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142765422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The seventh blind test of crystal structure prediction: structure generation methods.","authors":"Lily M Hunnisett, Jonas Nyman, Nicholas Francia, Nathan S Abraham, Claire S Adjiman, Srinivasulu Aitipamula, Tamador Alkhidir, Mubarak Almehairbi, Andrea Anelli, Dylan M Anstine, John E Anthony, Joseph E Arnold, Faezeh Bahrami, Michael A Bellucci, Rajni M Bhardwaj, Imanuel Bier, Joanna A Bis, A Daniel Boese, David H Bowskill, James Bramley, Jan Gerit Brandenburg, Doris E Braun, Patrick W V Butler, Joseph Cadden, Stephen Carino, Eric J Chan, Chao Chang, Bingqing Cheng, Sarah M Clarke, Simon J Coles, Richard I Cooper, Ricky Couch, Ramon Cuadrado, Tom Darden, Graeme M Day, Hanno Dietrich, Yiming Ding, Antonio DiPasquale, Bhausaheb Dhokale, Bouke P van Eijck, Mark R J Elsegood, Dzmitry Firaha, Wenbo Fu, Kaori Fukuzawa, Joseph Glover, Hitoshi Goto, Chandler Greenwell, Rui Guo, Jürgen Harter, Julian Helfferich, Detlef W M Hofmann, Johannes Hoja, John Hone, Richard Hong, Geoffrey Hutchison, Yasuhiro Ikabata, Olexandr Isayev, Ommair Ishaque, Varsha Jain, Yingdi Jin, Aling Jing, Erin R Johnson, Ian Jones, K V Jovan Jose, Elena A Kabova, Adam Keates, Paul F Kelly, Dmitry Khakimov, Stefanos Konstantinopoulos, Liudmila N Kuleshova, He Li, Xiaolu Lin, Alexander List, Congcong Liu, Yifei Michelle Liu, Zenghui Liu, Zhi Pan Liu, Joseph W Lubach, Noa Marom, Alexander A Maryewski, Hiroyuki Matsui, Alessandra Mattei, R Alex Mayo, John W Melkumov, Sharmarke Mohamed, Zahrasadat Momenzadeh Abardeh, Hari S Muddana, Naofumi Nakayama, Kamal Singh Nayal, Marcus A Neumann, Rahul Nikhar, Shigeaki Obata, Dana O'Connor, Artem R Oganov, Koji Okuwaki, Alberto Otero-de-la-Roza, Constantinos C Pantelides, Sean Parkin, Chris J Pickard, Luca Pilia, Tatyana Pivina, Rafał Podeszwa, Alastair J A Price, Louise S Price, Sarah L Price, Michael R Probert, Angeles Pulido, Gunjan Rajendra Ramteke, Atta Ur Rehman, Susan M Reutzel-Edens, Jutta Rogal, Marta J Ross, Adrian F Rumson, Ghazala Sadiq, Zeinab M Saeed, Alireza Salimi, Matteo Salvalaglio, Leticia Sanders de Almada, Kiran Sasikumar, Sivakumar Sekharan, Cheng Shang, Kenneth Shankland, Kotaro Shinohara, Baimei Shi, Xuekun Shi, A Geoffrey Skillman, Hongxing Song, Nina Strasser, Jacco van de Streek, Isaac J Sugden, Guangxu Sun, Krzysztof Szalewicz, Benjamin I Tan, Lu Tan, Frank Tarczynski, Christopher R Taylor, Alexandre Tkatchenko, Rithwik Tom, Mark E Tuckerman, Yohei Utsumi, Leslie Vogt-Maranto, Jake Weatherston, Luke J Wilkinson, Robert D Willacy, Lukasz Wojtas, Grahame R Woollam, Zhuocen Yang, Etsuo Yonemochi, Xin Yue, Qun Zeng, Yizu Zhang, Tian Zhou, Yunfei Zhou, Roman Zubatyuk, Jason C Cole","doi":"10.1107/S2052520624007492","DOIUrl":"10.1107/S2052520624007492","url":null,"abstract":"<p><p>A seventh blind test of crystal structure prediction was organized by the Cambridge Crystallographic Data Centre featuring seven target systems of varying complexity: a silicon and iodine-containing molecule, a copper coordination complex, a near-rigid molecule, a cocrystal, a polymorphic small agrochemical, a highly flexible polymorphic drug candidate, and a polymorphic morpholine salt. In this first of two parts focusing on structure generation methods, many crystal structure prediction (CSP) methods performed well for the small but flexible agrochemical compound, successfully reproducing the experimentally observed crystal structures, while few groups were successful for the systems of higher complexity. A powder X-ray diffraction (PXRD) assisted exercise demonstrated the use of CSP in successfully determining a crystal structure from a low-quality PXRD pattern. The use of CSP in the prediction of likely cocrystal stoichiometry was also explored, demonstrating multiple possible approaches. Crystallographic disorder emerged as an important theme throughout the test as both a challenge for analysis and a major achievement where two groups blindly predicted the existence of disorder for the first time. Additionally, large-scale comparisons of the sets of predicted crystal structures also showed that some methods yield sets that largely contain the same crystal structures.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11789161/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142455733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polymorphism of Pb₅(PO₄)₃OH_δ within the LK-99 mixture.","authors":"Mingyu Xu, Haozhe Wang, Cameron Vojvodin, Jayasubba Reddy Yarava, Tuo Wang, Weiwei Xie","doi":"10.1107/S2052520624010023","DOIUrl":"10.1107/S2052520624010023","url":null,"abstract":"<p><p>During the synthetic exploration targeting the polycrystalline compound LK-99, an unexpected phase, Pb₅(PO₄)₃OH_δ, was identified as a byproduct. We elucidated the composition of this compound through single-crystal X-ray diffraction analysis. Subsequent synthesis of the target compounds was achieved via high-temperature solid-state pellet reactions. The newly identified Pb₅(PO₄)₃OH_δ has an orthorhombic crystal structure with space group Pnma, representing a unique structure differing from the hexagonal apatite phases of Pb₁₀(PO₄)₆O and Pb₅(PO₄)₃OH. Comprehensive temperature- and magnetic-field-dependent magnetization studies unveiled a temperature-independent magnetic characteristic of Pb₅(PO₄)₃OH_δ. Solid-state nuclear magnetic resonance spectroscopy was employed to decipher the origins of the phase stability and confirm the presence of hydrogen atoms in Pb₅(PO₄)₃OH_δ. These investigations revealed the presence of protonated oxygen sites, in addition to the interstitial water molecules within the structure, which may play critical roles in stabilizing the orthorhombic phase.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11789162/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142765350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The incommensurate composite Y_xOs₄B₄ (x = 1.161).","authors":"Berthold Stöger, Oksana Sologub, Leonid Salamakha","doi":"10.1107/S205252062400982X","DOIUrl":"10.1107/S205252062400982X","url":null,"abstract":"<p><p>Y_xOs₄B₄ (x = 1.161) crystallizes as a tetragonal incommensurate composite of columns of Y atoms extending along [001] in an Os₄B₄ framework. The structure was refined using the superspace approach. The basic structure of the Y subsystem can be idealized as having I4/mmm symmetry, with a crystallographically unique Y atom located on the 4/mmm position. The actual superspace symmetry is P4₂/nmc(00σ₃)s0s0. The Y atoms feature only subtle positional modulation in the [001] direction. The Os₄B₄ subsystem [P4₂/ncm(00σ₃)00ss superspace symmetry] is built of columns of edge-sharing Os₄ tetrahedra extending along [001] and B₂ dumbbells. The Os₄ tetrahedra feature pronounced positional modulation with a distinct variation of the Os-Os bond lengths. Modulation of the B₂ dumbbells is best described as a rotation about the [001] axis.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11789166/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142602588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The seventh blind test highlights exciting developments in crystal structure prediction.","authors":"Mihails Arhangelskis","doi":"10.1107/S2052520624011570","DOIUrl":"https://doi.org/10.1107/S2052520624011570","url":null,"abstract":"<p><p>Two reports on the seventh blind test on crystal structure prediction extensively discuss the cutting-edge avant-garde methods of structure generation and energy ranking.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142765425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A contribution to the crystal chemistry and topology of organic thiosulfates: bis(1-methylpiperazinium)·S₂O₃·H₂O versus 1-methylpiperazinediium·S₂O₃·3H₂O.","authors":"Dmitri O Charkin, Alexandru M Banaru, Semen A Ivanov, Vadim E Kireev, Sergey M Aksenov","doi":"10.1107/S2052520624007443","DOIUrl":"https://doi.org/10.1107/S2052520624007443","url":null,"abstract":"<p><p>Single crystals of two new compounds, (C₅H₁₄N₂)S₂O₃·H₂O (1) and (C₅H₁₃N₂)₂S₂O₃·3H₂O (2), were isolated from the reaction products of 1-methylpiperazine, sulfuric acid, and barium thiosulfate in aqueous media. The crystal structures have been determined by single-crystal X-ray diffraction. In agreement to the previous observations, the organic template may contribute to the formation of thiosulfates both as mono- and diprotonated species, but this is the first case where both products are reported for the same organic compound. In both structures 1 and 2, complex nets of hydrogen bonds involve all cations, anions and water molecules. Comparisons are made to the structures of other thiosulfates containing mono- or diprotonated diamine species.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142765263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conformational disorder in quercetin dihydrate revealed from ultrahigh-resolution synchrotron diffraction.","authors":"Yvon Bibila Mayaya Bisseyou, Jonathan Wright, Christian Jelsch","doi":"10.1107/S2052520624010011","DOIUrl":"https://doi.org/10.1107/S2052520624010011","url":null,"abstract":"<p><p>Quercetin, a bioflavonoid abundant in plants, boasts antioxidant properties and plays a crucial role in various biological systems. The diffraction data of a quercetin dihydrate crystal have been measured at 20 (2) K to ultrahigh resolution (0.30 Å) using a synchrotron X-ray source. After meticulous multipolar refinement of the charge density, Fourier residual electron density peaks were identified, particularly at the position of hydrogen atom H15 of the catechol ring. This observation revealed a subtle disorder in the molecule, prompting the modelling of the catechol ring in two positions with occupancy percentages of 98.4% and 1.6% in the anti and syn conformations, respectively. Intermolecular interactions are analysed using Hirshfeld fingerprint plots and enrichment ratios. With the presence of numerous O-H...O hydrogen bonds, the packing shows good electrostatic complementarity between the quercetin molecule and its surroundings. The parallel displaced stacking interaction between two anti-quercetin molecules related by a translation along the a axis is, however, not attractive for its electrostatic contribution. The syn conformation shows more attractive quercetin dimers than the anti one. On the other hand, electrostatic interactions between quercetin and the two water molecules are stronger in the anti conformation. The electrostatic interactions of quercetin with human inositol polyphosphate multikinase were analysed in the structure of the complex found in the Protein Data Bank and compared with those the take place in the quercetin crystal packing.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142765268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structures of hexamethyl-[1,1'-biphenyl]-4,4'-diammonium salts.","authors":"Rajakumar Kanthapazham, Artyom A Osipov, Dmitry A Zherebtsov, Andrey N Efremov, Sergey A Nayfert, Sergey A Adonin, Dar'ya V Spiridonova, Sergey V Atapin","doi":"10.1107/S2052520624009818","DOIUrl":"https://doi.org/10.1107/S2052520624009818","url":null,"abstract":"<p><p>The crystal structures of nine hexamethyl-[1,1'-biphenyl]-4,4'-diammonium (HMB) salts are described: the iodide (2), triiodide (3), succinate (4), fumarate (5), tetravanadate (6), hydroterephthalate (7) and perylenetetracarboxylate (8), as well as pentamethyl-[1,1'-biphenyl]-4,4'-diammonium iodide (1) and the metal-organic framework sodium diacetylenedisalicylate-HMB (9). HMB carbonate (10) has been synthesized as an important intermediate for a promising anti-metal-organic framework (`anti-MOF'). All the described compounds are characterized by high solubility in water. The results suggest that, during crystallization, crystallohydrates are formed from water. Compounds 6 and 9 are characterized by the presence of a rigid framework; compound 6 has an open framework structure filled with water molecules. Synchronous thermal analyses of compounds 2, 4, 6, 7, 8 and 10 allowed the identification of similarities in the mechanisms of thermolysis. At about 80-180°C, the loss of crystallization water molecules occurs. Between 180 and 250°C, a methyl group (methyl cation) is split off from the quaternary ammonium salt to form tetramethylbenzidinium. In the case of the iodides and salts of organic acids, the second thermolysis product is the methyl ester of this acid (methyliodide, dimethyl carbonate), which easily evaporates. In the range 240-355°C, tetramethylbenzidinium evaporates without decomposition.</p>","PeriodicalId":7320,"journal":{"name":"Acta crystallographica Section B, Structural science, crystal engineering and materials","volume":" ","pages":""},"PeriodicalIF":1.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142765419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}