Acta Crystallographica Section B-structural Science最新文献_第6页

Symmetriebeziehungen zwischen verwandten Kristallstrukturen. Anwendungen der kristallographischen Gruppentheorie in der Kristallchemie unter Verwendung von Textvorlagen von Hans Wondratschek und Hartmut Bärnighausen. Von Ulrich Müller. Pp. 368. Wiesbaden: Vieweg + Teubner Verlag, 2012. Price (paperb 相关水晶结构之间的对称关系。应用水晶同体理论在结晶化学中Ulrich mullerPp工作. 368 .2012年薇德老出版社Price (paperb

IF 1.9 3区化学

Acta Crystallographica Section B-structural Science Pub Date : 2012-06-01 DOI: 10.1107/S0108768112018551

P. Paufler

引用次数: 5

Relation between photochromic properties and molecular structures in salicylideneaniline crystals. 水杨基苯胺晶体的光致变色性质与分子结构的关系。

IF 1.9 3区化学

Acta Crystallographica Section B-structural Science Pub Date : 2012-06-01 Epub Date: 2012-05-04 DOI: 10.1107/S0108768112010993

Kohei Johmoto, Takashi Ishida, Akiko Sekine, Hidehiro Uekusa, Yuji Ohashi

{"title":"Relation between photochromic properties and molecular structures in salicylideneaniline crystals.","authors":"Kohei Johmoto, Takashi Ishida, Akiko Sekine, Hidehiro Uekusa, Yuji Ohashi","doi":"10.1107/S0108768112010993","DOIUrl":"https://doi.org/10.1107/S0108768112010993","url":null,"abstract":"The crystal structures of the salicylideneaniline derivatives N-salicylidene-4-tert-butyl-aniline (1), N-3,5-di-tert-butyl-salicylidene-3-methoxyaniline (2), N-3,5-di-tert-butyl-salicylidene-3-bromoaniline (3), N-3,5-di-tert-butyl-salicylidene-3-chloroaniline (4), N-3,5-di-tert-butyl-salicylidene-4-bromoaniline (5), N-3,5-di-tert-butyl-salicylidene-aniline (6), N-3,5-di-tert-butyl-salicylidene-4-carboxyaniline (7) and N-salicylidene-2-chloroaniline (8) were analyzed by X-ray diffraction analysis at ambient temperature to investigate the relationship between their photochromic properties and molecular structures. A clear correlation between photochromism and the dihedral angle of the two benzene rings in the salicylideneaniline derivatives was observed. Crystals with dihedral angles less than 20° were non-photochromic, whereas those with dihedral angles greater than 30° were photochromic. Crystals with dihedral angles between 20 and 30° could be either photochromic or non-photochromic. Inhibition of the pedal motion by intra- or intermolecular steric hindrance, however, can result in non-photochromic behaviour even if the dihedral angle is larger than 30°.","PeriodicalId":7107,"journal":{"name":"Acta Crystallographica Section B-structural Science","volume":"68 Pt 3","pages":"297-304"},"PeriodicalIF":1.9,"publicationDate":"2012-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1107/S0108768112010993","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30630827","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}

引用次数: 32

Structural chemistry of A2MX4 compounds (X = O, F) with isolated tetrahedral anions: search for the densest structure types. 具有孤立四面体阴离子的A2MX4化合物(X = O, F)的结构化学:寻找最密集的结构类型。

IF 1.9 3区化学

Acta Crystallographica Section B-structural Science Pub Date : 2012-06-01 Epub Date: 2012-05-17 DOI: 10.1107/S010876811201419X

Vladimir Nalbandyan, Anastasiya Novikova

{"title":"Structural chemistry of A2MX4 compounds (X = O, F) with isolated tetrahedral anions: search for the densest structure types.","authors":"Vladimir Nalbandyan, Anastasiya Novikova","doi":"10.1107/S010876811201419X","DOIUrl":"https://doi.org/10.1107/S010876811201419X","url":null,"abstract":"The packing density of various structures is important not only for understanding and the prediction of high-pressure phase transitions, but also because of its reported correlation with thermodynamic stability. Plotting the cube root of formula volume against the cation radii (R) for nine morphotropic series with isolated tetrahedral anions, A(2)MO(4) (M = Si, Ge, S, Se, Cr, Mn, Mo, W) and A(2)BeF(4), permits the comparison of packing densities for 13 structure types (about 80 individual compounds and several solid solutions) stable at (or near) ambient temperature. The spinel type is the densest. The next densest types are those of K(2)MoO(4), Tl(2)CrO(4), β-Ca(2)SiO(4), β-K(2)SO(4), Ag(2)CrO(4) and Sr(2)GeO(4). In three series (M = Ge, Mo, W) the densest type comes with somewhat intermediate values of R, and not the largest, in contrast to the classical homology rule. Another contradiction with traditional views is that some of the densest phases have abnormally low overall binding energies. The correlation between packing density and coordination number (CN) is better when CN of A counts entire MX(4) groups rather than individual X atoms; many, but not all, A(2)MX(4) structures have binary A(2)M analogues (of course, A and M are not necessarily the same in these structure types). The most frequent arrangement of A around M is of the Ni(2)In type: a (distorted) pentacapped trigonal prism.","PeriodicalId":7107,"journal":{"name":"Acta Crystallographica Section B-structural Science","volume":"68 Pt 3","pages":"227-39"},"PeriodicalIF":1.9,"publicationDate":"2012-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1107/S010876811201419X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30632032","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}

引用次数: 11

Voronoi-Dirichlet tesselation as a tool for investigation of polymorphism in molecular crystals with CwHxNyOz composition and photochromic properties. Voronoi-Dirichlet镶嵌作为研究CwHxNyOz组成和光致变色分子晶体多态性的工具。

IF 1.9 3区化学

Acta Crystallographica Section B-structural Science Pub Date : 2012-06-01 Epub Date: 2012-05-17 DOI: 10.1107/S0108768112014711

Viktor N Serezhkin, Larisa B Serezhkina, Anna V Vologzhanina

{"title":"Voronoi-Dirichlet tesselation as a tool for investigation of polymorphism in molecular crystals with CwHxNyOz composition and photochromic properties.","authors":"Viktor N Serezhkin, Larisa B Serezhkina, Anna V Vologzhanina","doi":"10.1107/S0108768112014711","DOIUrl":"https://doi.org/10.1107/S0108768112014711","url":null,"abstract":"The non-bonded interactions in five sets of polymorph substances with photochromic properties have been investigated within the Voronoi-Dirichlet approach. Twenty compounds with the general formula C(w)H(x)N(y)O(z) were analyzed. Among ten possible types of non-bonded interactions at least five types are observed in the crystal structures of compounds under discussion. For all the structures the majority of interactions involve H atoms, namely London forces (H...H and H...C) and hydrogen bonds (H...O and H...N). A conformational polymorph was stated to be characterized by a unique set of inter- and intramolecular non-bonded interactions. It was quantitatively demonstrated that molecules in the same conformation can pack in a different way, and, vice versa, the change in conformation of a molecule does not prevent a substance from realising the same set of intermolecular contacts. In accordance with the data obtained for 2,4-dinitrobenzylpyridine derivatives, only conformational polymorphs with an intramolecular N...N interaction between a nitro group and a pyridine are photochromic.","PeriodicalId":7107,"journal":{"name":"Acta Crystallographica Section B-structural Science","volume":"68 Pt 3","pages":"305-12"},"PeriodicalIF":1.9,"publicationDate":"2012-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1107/S0108768112014711","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30630828","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}

引用次数: 36

Effect of pressure on crystalline L- and DL-serine: revisited by a combined single-crystal X-ray diffraction at a laboratory source and polarized Raman spectroscopy study. 压力对L-丝氨酸和dl -丝氨酸晶体的影响:通过实验室源单晶x射线衍射和偏振拉曼光谱研究重新审视。

IF 1.9 3区化学

Acta Crystallographica Section B-structural Science Pub Date : 2012-06-01 Epub Date: 2012-05-17 DOI: 10.1107/S0108768112015960

Boris A Zakharov, Boris A Kolesov, Elena V Boldyreva

引用次数: 30

Parallel stacking interactions in square-planar transition-metal complexes containing fused chelate and C6-aromatic rings. 含熔融螯合物和c6 -芳环的方形平面过渡金属配合物的平行堆叠相互作用。

IF 1.9 3区化学

Acta Crystallographica Section B-structural Science Pub Date : 2012-06-01 Epub Date: 2012-05-04 DOI: 10.1107/S0108768112012281

Dušan N Sredojević, Dubravka Z Vojislavljević, Zoran D Tomić, Snezana D Zarić

引用次数: 21

Invariom modeling of ceftazidime pentahydrate: molecular properties from a 200 second synchrotron microcrystal experiment. 五水头孢他啶的不变性建模:来自200秒同步微晶实验的分子特性。

IF 1.9 3区化学

Acta Crystallographica Section B-structural Science Pub Date : 2012-06-01 Epub Date: 2012-05-17 DOI: 10.1107/S0108768112017831

C J Schürmann, K Pröpper, T Wagner, B Dittrich

引用次数: 11

Phase transition at high pressure in Cu2CO3(OH)2 related to the reduction of the Jahn-Teller effect. Cu2CO3(OH)2中高压下的相变与Jahn-Teller效应的降低有关。

IF 1.9 3区化学

Acta Crystallographica Section B-structural Science Pub Date : 2012-06-01 Epub Date: 2012-05-04 DOI: 10.1107/S0108768112011226

Marco Merlini, Natale Perchiazzi, Michael Hanfland, Alexei Bossak

{"title":"Phase transition at high pressure in Cu2CO3(OH)2 related to the reduction of the Jahn-Teller effect.","authors":"Marco Merlini, Natale Perchiazzi, Michael Hanfland, Alexei Bossak","doi":"10.1107/S0108768112011226","DOIUrl":"https://doi.org/10.1107/S0108768112011226","url":null,"abstract":"Hydroxycarbonates with the general formula Me(2)(CO(3))(OH)(2) are widely used materials in industrial processes and are widespread in nature. The Cu term, malachite, Cu(2)CO(3)(OH)(2), is monoclinic, P2(1)/a. Substitution of Cu(2+) with other bivalent cations such as Mg, Zn, Fe, Cu or Ni is possible and leads to a different structure type, rosasite, P2(1)/a or P2(1)/b11 in the same cell setting as malachite. Rosasite structure is topologically similar to malachite, but the symmetry elements are oriented differently with respect to structural units. The stability of the malachite-like structure (MS) compared with the rosasite-like structure (RS) has been suggested to be related to the Jahn-Teller effect in CuO(6) coordination polyhedra. For this reason the hypothesis of the phase transition of malachite, Cu(2)CO(3)(OH)(2), to a rosasite structure at high pressure, as a result of the reduced Jahn-Teller effect, has been tested and confirmed by powder and single-crystal diffraction structural studies: above 6 GPa the malachite structure is no longer stable and transforms to a RS structure. RS Cu(2)CO(3)(OH)(2) is 3% more dense than malachite and the bulk modulus is remarkably higher, 80 (2) GPa compared with 48 (4) GPa. The longer apical Cu-O bonds in the distorted Me1 octahedral site are progressively shortened with increasing pressure, revealing a decrease in the Jahn-Teller effect at high pressure. The transition has a first-order character, is reversible with a significant hysteresis, and there is no evidence of any intermediate phase between the two structures. We then have further evidence that in the Me(2)(CO(3))(OH)(2) compounds, the two main structural types, MS and RS, are closely related. The former structure is stabilized only when Cu is the prevalent cation in the octahedral sites, and it can transform directly to the RS as a function of thermodynamic changes.","PeriodicalId":7107,"journal":{"name":"Acta Crystallographica Section B-structural Science","volume":"68 Pt 3","pages":"266-74"},"PeriodicalIF":1.9,"publicationDate":"2012-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1107/S0108768112011226","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30632036","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}

引用次数: 27

Structure of (Ga2O3)2(ZnO)13 and a unified description of the homologous series (Ga2O3)2(ZnO)(2n + 1). (Ga2O3)2(ZnO)13的结构和同源系列(Ga2O3)2(ZnO)(2n + 1)的统一描述。

IF 1.9 3区化学

Acta Crystallographica Section B-structural Science Pub Date : 2012-06-01 Epub Date: 2012-05-17 DOI: 10.1107/S0108768112016084

Yuichi Michiue, Noboru Kimizuka, Yasushi Kanke, Takao Mori

{"title":"Structure of (Ga2O3)2(ZnO)13 and a unified description of the homologous series (Ga2O3)2(ZnO)(2n + 1).","authors":"Yuichi Michiue, Noboru Kimizuka, Yasushi Kanke, Takao Mori","doi":"10.1107/S0108768112016084","DOIUrl":"https://doi.org/10.1107/S0108768112016084","url":null,"abstract":"The structure of (Ga(2)O(3))(2)(ZnO)(13) has been determined by a single-crystal X-ray diffraction technique. In the monoclinic structure of the space group C2/m with cell parameters a = 19.66 (4), b = 3.2487 (5), c = 27.31 (2) Å, and β = 105.9 (1)°, a unit cell is constructed by combining the halves of the unit cell of Ga(2)O(3)(ZnO)(6) and Ga(2)O(3)(ZnO)(7) in the homologous series Ga(2)O(3)(ZnO)(m). The homologous series (Ga(2)O(3))(2)(ZnO)(2n + 1) is derived and a unified description for structures in the series is presented using the (3+1)-dimensional superspace formalism. The phases are treated as compositely modulated structures consisting of two subsystems. One is constructed by metal ions and another is by O ions. In the (3 + 1)-dimensional model, displacive modulations of ions are described by the asymmetric zigzag function with large amplitudes, which was replaced by a combination of the sawtooth function in refinements. Similarities and differences between the two homologous series (Ga(2)O(3))(2)(ZnO)(2n + 1) and Ga(2)O(3)(ZnO)(m) are clarified in (3 + 1)-dimensional superspace. The validity of the (3 + 1)-dimensional model is confirmed by the refinements of (Ga(2)O(3))(2)(ZnO)(13), while a few complex phenomena in the real structure are taken into account by modifying the model.","PeriodicalId":7107,"journal":{"name":"Acta Crystallographica Section B-structural Science","volume":"68 Pt 3","pages":"250-60"},"PeriodicalIF":1.9,"publicationDate":"2012-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1107/S0108768112016084","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30632034","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}

引用次数: 6

Form, function and functionality of two dimeric toluene-2,4-diisocyanate polymorphs. 两种二聚甲苯-2,4-二异氰酸酯多态物的形态、功能和功能。

IF 1.9 3区化学

Acta Crystallographica Section B-structural Science Pub Date : 2012-04-01 Epub Date: 2012-03-20 DOI: 10.1107/S0108768112008592

Liana Vella-Zarb, Robert E Dinnebier

引用次数: 4