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1.
Vanessa Renee Little Hilary Jenkins Keith Vaughan 《Journal of chemical crystallography》2008,38(6):447-452
Abstract The crystal structures of methyl 4-{(E)-2-(4-methylpiperazino)-1-diazenyl}benzoate (2a) and 1,4-di[(E)-2-(2-nitrophenyl)-1-diazenyl]piperazine (3a) have been determined by single crystal X-ray diffraction analysis. The bis-triazene (3a) adopts an unusual pseudo-boat conformation in the piperazine ring, with a dihedral angle of 52.20(0.06)° between the two
planes defined within the piperazine ring. The crystal structures of 2a and 3a are compared with the structure of the triazene (4) and the closely related bis-triazene (5). The piperazine ring of 2a adopts a typical chair conformation, whereas the piperazine ring of 3a adopts an unusual boat conformation. Crystal data: 2a C13H18N4O2, monoclinic, space group P21
/n, a = 13.849(3) ?, b = 6.577(1) ?, c = 14.904(3) ?, α = 90°, β = 96.098(3)°, γ = 90° and V = 1,349.8(4) ?3, for Z = 4. 3a C16H16N8O4, triclinic, space group P-1, a = 7.6066(6) ?, b = 8.3741(7) ?, c = 14.507(1) ?, α = 78.673(1)°, β = 81.877(1)°, γ = 73.445(1)° and V = 865.0(1) ?3, for Z = 2.
Index abstract
The crystal structures of methyl 4-{(E)-2-(4-methylpiperazino)-1-diazenyl}benzoate (2a) and 1,4-di[(E)-2-(2-nitrophenyl)-1-diazenyl]piperazine (3a) have been determined by single crystal X-ray diffraction analysis. 相似文献
2.
Resul Sevinçek Muhittin Aygün Serap Alp Canan Kazak 《Journal of chemical crystallography》2011,41(8):1140-1144
Abstract
Molecular and crystal structure of 4-[(p-N,N-dimethylamino)benzylidene]-2-phenyloxazol-5-one, C18H16N2O2, have been determined by single crystal X-ray diffraction study. The title compound is monoclinic, with a = 12.1704(23) ?, b = 3.9810(5) ?, c = 30.9603(56) ?, β = 101.176(15)°, Z = 4, D x = 1.32 g/cm3, μ(Mo Kα) = 0.087 mm−1, and space group is P121/c1. The structure was solved by direct methods and refined to a final R = 0.047 for 3166 reflections with I > 2σ(I). The crystal structure is stabilized by C–H⋯O and C–H⋯N type intra-molecular, C–H⋯O type inter-molecular interactions. To enlighten the flexibility and the geometric isomerism (E or Z) of the title compound, the selected torsion angle is varied from −180 to 180° in every 10° separately and molecular energy profile is calculated and analyzed. 相似文献3.
Günseli Turgut Cin Seda Demirel Topel Abban Cakıcı Arzu Özek Yıldırım Ahmet Karadağ 《Journal of chemical crystallography》2012,42(4):372-380
Abstract
Two novel ferrocenyl substituted N-acetyl-2-pyrazolines, N-acetyl-3-(2-furyl)-5-ferrocenyl-2-pyrazoline (3) and N-acetyl-3-(2-thienyl)-5-ferrocenyl-2-pyrazoline (4), have been synthesized and characterized by FTIR, 1H-NMR, 13C-NMR techniques, elemental analysis and X-ray structure analysis. Thermal properties of these compounds have been determined by TGA, DTA and DSC analysis. Compound 3 (C19H18N2O2Fe) crystallizes in the monoclinic space group P21/c and Z = 4, with a = 8.6970(4) ?, b = 18.4725(9) ?, c = 11.0041(5) ?, β = 110.942(3)°. Compound 4 (C19H18N2OSFe) crystallizes in the orthorhombic space group Fdd2 and Z = 16, with a = 84.242(2) ?, b = 13.5416(5) ?, c = 5.9405(2) ?, β = 90°. In terms of crystal packing, each compound shows different molecular arrangement, which are stabilized by C–H···O intermolecular weak hydrogen bonds, and/or C–H···π interactions. 相似文献4.
Ilya N. Egorov Vladimir L. Rusinov Pavel A. Slepukhin Oleg N. Chupakhin 《Journal of chemical crystallography》2010,40(4):387-390
Abstract
The diastereoselective synthesis, NMR and X-ray structure of (S)-2-((S)-2-(N-Ts-amino)-3-methylbutanoyl)-3-(1H-indol-3-yl)-6-phenyl-3,4-dihydro-1,2,4-triazin-5(2H)-one—a potential antivirus agent are reported. The compound crystallizes in the triclinic space group P1 with unit cell parameters: a = 5.9259(6) ?, b = 9.6370(12) ?, c = 12.9541(9) ?, α = 109.210(9)°, β = 90.804(7)°, γ = 105.074(10)° and Z = 1. 相似文献5.
Wei Xiong Yan Su Zhong Zhang Zilu Chen Fupei Liang Lixia Wang 《Journal of chemical crystallography》2011,41(10):1510-1514
Abstract
The reactions of a new compound of N-Carboxyphenylenesulfonyl-S-Carboxymethyl-l-Cysteine (Cs-cmc) with Zn(II) or Co(II) salts in the presence of 4,4′-bipyridine (4,4′-bipy) led to the decomposition of Cs-cmc and produced [Zn(4,4′-bipy)(H2O)4]X2 (X = p-sulfamoylbenzoate) 1 and [Co(4,4′-bipy)(H2O)4]Y·H2O (Y = p-sulfonatobenzoate) 2, in which the decomposition products of Cs-cmc exist as free counter-anions. The single crystal X-ray diffraction analyses revealed that compound 1 crystallizes in monoclinic C2/c space group with a = 18.748(4) ?, b = 11.520(2) ?, c = 12.751(3) ?, β = 90.290(4)°, V = 2753.9(10) ?, Z = 4 and compound 2 crystallizes in orthorhombic Pca21 space group with a = 12.114(3) ?, b = 11.369(2) ?, c = 14.770(3) ?, V = 2034.1(7) ?, Z = 4. It was revealed that 1D chains were constructed from metal ions and 4,4′-bipy in both compounds. The 1D chains interact with the counter-anions by hydrogen bonds, forming 3D supramolecular structures. 相似文献6.
R. Alan Howie Marcus V. N. de Souza Camilo H. da Silva Lima James L. Wardell Solange M. S. V. Wardell 《Journal of chemical crystallography》2012,42(4):394-400
Abstract
The molecule of (E)-3-(3-MeOC6H4CH=CHCO)-benzotriazole 1-oxide, 2, has a very near planar structure, while the 2-nitrophenyl ring is rotated out of the plane of the remaining atoms in (E)-3-(2-O2NC6H4CH=CHCO)-benzotriazole 1-oxide, 1. The nitrogen oxide bond lengths in 1 and 2 are 1.258 (6) and 1.2683 (15) ?, respectively, and are in the region found for related compounds. There are no strong intermolecular hydrogen-bonds in either compound, instead there are weak C–H···O intermolecular hydrogen-bonds and π···π stacking interactions in 1, and C–H···O, C–H···π, and π···π stacking interactions in 2. Different three-dimensional arrays are generated in each case. Compound 1 crystallises in the orthorhombic space group Pna21, with a = 25.061 (2) ?, b = 3.6997 (2) ?, c = 14.2623 (12) ? and Z = 4. Compound 2 crystallises in the triclinic space group P-1, with a = 5.7297 (3) ?, b = 10.8440 (6) ?, c = 11.4965 (6) ?, α = 89.689 (3)°, β = 76.019 (3)°, γ = 75.047 (3)°, Z = 2. 相似文献7.
Shu-Ni Li Quan-Guo Zhai Man-Cheng Hu Yu-Cheng Jiang 《Journal of chemical crystallography》2011,41(1):12-16
Abstract
Two novel complexes constructed from the sulfonamide Schiff base ligand H 2 L, N-[2-(5-bromo-2-hydroxybenzylideneamino)ethyl]-4-methylbenzene-sulfonamide, [Cu(HL)2] (1) and [CuL(H2O)] (2) are synthesized and characterized via X-ray single-crystal diffraction, elemental analysis, FT-IR and UV–Vis. 1 and 2 both form 1-D supramolecular architectures by π–π stacking interactions. 1 and 2 both crystallize in monoclinic, with space group C2/c and P2/c for 1 and 2, with unit cell parameters a = 27.640(18) ?, b = 7.907(5) ?, c = 17.945(14) ?, β = 118.27(2)°, V = 3454(4) ?3, Z = 4 for 1, and a = 16.758(5) ?, b = 7.272(2) ?, c = 15.080(4) ?, β = 106.334(5)°, V = 1763.6(9) ?3, Z = 4 for 2. 相似文献8.
Irena Ćaleta Dominik Cinčić Grace Karminski-Zamola Branko Kaitner 《Journal of chemical crystallography》2008,38(10):775-780
Abstract Two novel benzothiazoles 2-chloro-N-(benzothiazol-2-yl)benzamide (1) and 2-chloro-N-(6-cyanobenzothiazol-2-yl)benzamide (2) were obtained in multistep synthesis. They were characterised by means of IR, 1H- and 13C-NMR spectroscopy and also by single-crystal X-ray diffraction. The compound 1 crystallises with triclinic space group P
, a = 9.5923(8) ?, b = 9.8583(8) ?, c = 13.8962(10) ?, α = 89.162(6)°, β = 77.741(7)°, γ = 80.064(7)°, V = 1264.5(2) ?3, Z = 4 and compound 2 crystallises as methanol solvate with monoclinic space group P 21/n, a = 7.5093(9) ?, b = 13.0211(14) ?, c = 16.032(2) ?, β = 92.717(10)°, V = 1565.9(3) ?3, Z = 4. Both crystal structures consist of discrete dimers connected into a three-dimensional network by intermolecular C–H···O
and C–H···X (X = Cl or S) hydrogen bonds and by face-to-face π–π stacking interactions.
Index Abstract The synthesis and structure of two novel N-(benzothiazol-2-yl)benzamides. Irena Ćaleta, Dominik Cinčić, GraceKarminski-Zamola and Branko Kaitner. Hydrogen bonds and
π–π interactions in N-(benzothiazol-2-yl)benzamides N-(benzothiazol-2-yl)benzamides.
相似文献
9.
Abstract
In order to investigate the intramolecular [4 + 2] cycloaddition, we prepared some new tertiary N-(5-substituted-2-furfuryl)-N-prop-2-ynyl-p-toluidines [Hergold-Brundić et al., Acta Cryst C56:e520, 2000; Mance and Jakopčić, Mol Divers 9:229, 2005; Mance, “unpublished results”] by the alkylation of secondary N-(5-substituted-2-furfuryl)-p-toluidines with the propargyl-bromide [Mance and Šindler-Kulyk, Synth Commun 26:923, 1996]. In the course of preparation of N-(5-methoxy-2-furfuryl)-N-prop-2-ynyl-p-toluidine [Mance, “unpublished results”], besides the main product (compound 1) (Scheme 1) we obtained N,N-di(prop-2-ynyl)-p-toluidine (compound 2) as the colourless crystals. The title compound 2, N,N-di(prop-2-ynyl)-p-toluidine, C13H13N, crystallizes in monoclinic C 2/c space group with unit cell parameters: a = 19.5319(9) ?, b = 7.5230(3) ?, c = 15.9000(7) ?, β = 112.554(5)°, V = 2157.64(18) ?3, Z = 8. The crystal structure is dominated by van der Waals forces only. The bond distances around amine N atom correspond to σ dominated bonds (1.467(2), 1.462(2) and 1.419(2) ?). The angles sum around amine N atom is in accord with sp3 hybridization (343°). 相似文献10.
Maciej Kubicki Grzegorz Dutkiewicz A. S. Praveen Anil N. Mayekar B. Narayana H. S. Yathirajan 《Journal of chemical crystallography》2012,42(5):432-437
Abstract
The Schiff base, 4-{(2E)-2-[1-(4-methoxyphenyl)ethylidene] hydrazinyl}-8-(trifluoromethyl)quinoline, crystallizes in two polymorphic forms depending on the solvent. One of these forms is monoclinic (1M), space group P21/c with a = 10.2906(10) ?, b = 8.9211(7) ?, c = 18.4838(15), β = 97.271(8)°, and the other is orthorhombic (1O), space group Pbca, unit-cell parameters: a = 13.6485(12) ?, b = 9.0588(9) ?, c = 27.400(2) ?. The molecules in either crystalline form have similar bond lengths and angles, but one is nearly planar while the other has a significant twist. In monoclinic form the dihedral angle between terminal ring planes is 17.26(8)° while in the orthorhombic one it is 26.11(5)°, and in this latter case the central chain is almost coplanar with the quinoline ring system while in the former these two planes are significantly twisted. The crystal structures of both forms are determined by the interplay of van der Waals forces and weak directional interactions C–H···F, π···π stacking, and—in the case of 1M—short intermolecular C–F···N contact. The crystals of 1M decomposes slowly into the powder while the other form is stable. The powder diffraction pattern of the product of decomposition of 1M is similar to that calculated for 1O. This suggests that the decomposition is a consequence of the phase transition of the less stable monoclinic into more stable orthorhombic form. 相似文献11.
Zhu-Ping Xiao Li-Cheng Yi Tian-Fang Yi Kai-Shuang Xiang Ze-Jun Huang Hai-Liang Zhu 《Journal of chemical crystallography》2012,42(4):323-329
Abstract
Crystalline hydrate of the title compound (5), C19H26N2O5·2(H2O), was structurally characterized by single crystal X-ray diffraction. It crystallizes in monoclinic system space group P 21/c with a = 7.3987(7) ?, b = 17.8691(16) ?, c = 17.0022(13) ?, β = 112.944(3)°, V = 2070.0(3) ?3, Z = 4, R 1 = 0.0592, wR 2 = 0.1016, and T = 298(2) K. The X-ray structure determination revealed that the center furanone ring is nearly coplanar with 3,4-dimethoxybenzene ring, making a dihedral angle of 0.860(69)°. Two kinds of centrosymmetric tetramers characterized by graph-set motifs of R 78(36) and R 46(32) are formed through O–H···O, O–H···N and C–H···O hydrogen bonding interactions, which generate a sheet of edge-fused rings parallel to the (011) plane. These sheets are further linked into a three dimensional network by C–H···π interactions. Nine 3-(3,4-dimethoxyphenyl)furan-2(5H)-ones were synthesized and fully characterized by elemental analysis, MS and 1H NMR. All of them were evaluated for antimicrobial activities against three Gram-positive organisms and a Gram-negative organism, and compound 5 was the most active against Staphylococcus aureus ATCC 25923. 相似文献12.
Zhan Shu Hai Yan Li Lin Lin Ma Wei Liang Chen Zhi Min Jin 《Journal of chemical crystallography》2009,39(5):384-388
Abstract The dl-lomenfloxacin hydrate is an innersalt, which crystallizes in space group C2/c with cell parameters a = 22.897(10), b = 8.682(1), c = 18.365(2) ?, β = 93.633(9)°, V = 3,705(3) ?3 and Z = 8. The piperazinyl ring adopts a chair conformation, and the quinolone ring is essentially planar. The plane defined by
C atoms of the piperazinyl ring is not coplanar with the quinolone ring. The carboxylate group shows two disorder parts, and
is not coplanar with the quinolone ring, the dihedral angle between them is 113.8°. The disorder carboxylate group is split
into two parts, the planes of which are skewed at the dihedral angles of 24.5 and 21.6° with the plane of the quinolone ring,
respectively. The IR of the title compound is measured and studied.
Index abstract The crystal structure of dl-lomenfloxacin hydrate is determined by X-ray diffraction. The IR is measured and shows great differences from previous studies.
相似文献
13.
Angela Tuzi Anna Andolfi Alessio Cimmino Antonio Evidente 《Journal of chemical crystallography》2010,40(1):15-18
Abstract
The X-ray crystal structure of phyllostin (8-hydroxy-3-methyl-2-oxo-2,3,4a,5,8,8a-hexahydro-benzo[1,4]dioxine-6-carboxylic acid methyl ester) is reported. Phyllostin was recently and for the first time isolated, together with phytotoxin phyllostoxin and the phyllostictines A–D, from the culture filtrates of Phyllosticta cirsii, a fungal pathogen isolated from diseased Cirsium arvense leaves and evaluated as biocontrol agent of this noxious perennial weed. Phyllostin crystallizes in the monoclinic space group P21 with unit cell parameters: a = 8.371(2), b = 7.026(1), c = 9.918(1) ?, β = 92.013(8)°, Z = 2. The final refinement converged to R1 = 0.0530 for 1026 observed reflections having I > 2σ(I). In the molecule two trans joined six-membered rings are present. The cyclohexene ring adopts a half-chair conformation. The 2-oxo-1,4-dioxan ring adopts a distorted half-chair conformation. The relative stereochemistry of the four chiral centers turns out to be 3R,4aS,8R,8aS. In the crystal packing molecules form infinite chains through O–H···O intermolecular hydrogen bonds. Chains run along the crystallographic a axis forming layers of molecules stacking in the [0 1 0] direction. 相似文献14.
Zahid H. Chohan Hazoor A. Shad Loic Toupet Taibi Ben Hadda Mehmet Akkurt 《Journal of chemical crystallography》2011,41(2):159-162
Abstract
The title compound (3), C17H14BrN3O4S, is a Schiff base compound of 5-bromosalicylaldehyde (1) and sulfamethoxazole (2). The structure of (3) was determined by spectral (IR, 1H and 13C NMR), elemental analyses and X-ray diffraction data. Compound (3) crystallizes in the monoclinic space group C2/c, with a = 31.936(3), b = 6.2571(5), c = 16.903(1) ?, β = 94.867(8), V = 3365.5(5) ?3, Z = 8. In the molecule of compound (3), the molecule is bent at the S atom with a C–SO2–NH–C torsion angle of −86.3(3)°. Pairs of molecules, related by inversion centres, form intermolecular N–H···N hydrogen bonds to produce a dimer. An intramolecular phenolic O–H···N hydrogen bond is also formed. Intermolecular hydrogen bonding and π–π stacking hold the molecules together. The average distance between stacked benzene ring planes is 3.625(2) ?. 相似文献15.
Annamária Krajníková Róbert Gyepes Katarína Győryová 《Journal of chemical crystallography》2010,40(8):650-655
Abstract
The syntheses and structural characterizations of two novel 2-bromobenzoatozinc(II) complexes—[Zn(2-BrC6H4COO)2] n (I) and [Zn(2-BrC6H4COO)2(mnad)]2 (II), where mnad is N-methylnicotinamide are reported. Compound (I) crystallized with a monoclinic lattice (space group P21/c) and is polymeric in solid state. Its cell parameters are: a = 7.37220(10) Å, b = 19.9639(3) Å, c = 30.2756(5) Å, β = 94.7510(7)°, V = 4440.59(12) Å3, Z = 4. The coordination environments of all zinc atoms are distorted tetrahedra built from four carboxylate oxygen atoms coming from four 2-bromobenzoato ligands. Compound (II) crystallized with a monoclinic lattice (space group P21/c) with a = 11.7488(2) Å, b = 20.3683(3) Å, c = 9.30130(10) Å, β = 100.3941(11)°, V = 2189.30(5) Å3, Z = 2. This dimeric molecule features a paddle-wheel [Zn2O8] cage in solid state; the coordination environment of the central atom is square pyramidal consisting of four carboxylate oxygen atoms and the pyridine N atom of the mnad ligand. 相似文献16.
Jerry P. Jasinski Ray J. Butcher Anil N. Mayekar H. S. Yathirajan B. Narayana B. K. Sarojini 《Journal of chemical crystallography》2009,39(10):761-765
Abstract The title compound, C18H18BrN3O3S, a derivative of 1,3,4-oxadiazole, crystallizes in the triclinic space group P-1 with unit cell parameters a = 6.8731(3), b = 8.9994(4), c = 15.7099(6) ?, α = 92.779(3)°, β = 130.575(3)°, γ = 107.868(4)°, Z = 2. The dihedral angle between the mean planes of the planar naphthyl and morpholine (chair) rings with the planar oxadiazol
ring is 50.1(8) and 76.8(6)°, respectively. The planar naphthyl ring is twisted 52.2(5)° with the mean plane of the morpholine
ring. A group of four intermolecular close contacts are observed between a bromine atom and hydrogen atoms from the closely
packed naphthyl, morpholine and oxy–methyl groups in the unit cell. These molecular interactions in concert with an additional
series of π–π stacking interactions that occur between the center of gravity of the two 6-membered rings of the naphthalene
group influence the twist angles of each of these three groups. A MOPAC AM1 calculation of the conformation energy of the
crystal structure [226.0128(9) kcal] compared to that of the minimum energy structure after geometry optimization [29.9744(1) kcal]
reveals a significantly reduced value. The twist angles of the three groups above also change after the AM1 calculation giving
support to the influence of both intermolecular C–H···Br short-range interactions and Cg π–π stacking interactions on these
angles which therefore play a role in stabilizing crystal packing.
Graphical Abstract Crystal structure of 5-{[(6-bromonaphthalen-2-yl)oxy]methyl}-3-(morpholin-4-ylmethyl)-1,3,4-oxadiazole-2(3H)-thione, C18H18BrN3O3S, is reported and its geometric and packing parameters described and compared to a MOPAC computational calculation.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
17.
Abstract
The mixed ligand dithiocarbamate complex was synthesized by the reaction between the ammonium salt of the dithiocarbamate ligands with mercury salt. There are two mercury complexes in the asymmetric unit with a compositional disorder between an ethyl group and a methyl group. A distorted tetrahedral geometry is found for each mercury atom defined by four sulphur atoms derived from two asymmetrically chelating dithiocarbamate ligands. IR spectra show thioureide υ(C–N) bands at 1491 cm−1 which is higher than observed in the simple complexes of the same ligands. The effect of alkyl substituents were observed in the magnetic unequivalence of the thioureide and phenyl units in the NMR spectroscopy. The molecules are related to each other by virtue of the compositional disorder which exists at three positions in the alkyl group across the unit. The compound crystallizes in the triclinic space group P-1 with a = 10.4764(10) ?, b = 11.0433(10) ?, c = 18.5566(17) ?, α = 97.8980(10)°, β = 95.3340(10)°, γ = 110.3010(10)°, and Z = 2. 相似文献18.
Rui Yuan Wei Lin Wei Yin Rong-cheng Bo Jing-jing Shi Xiao-fei Zhang Xiao-xiao Zhang Chao Wang Yu Wan Hui Wu 《Journal of chemical crystallography》2010,40(9):799-801
Abstract
The title compound 2-(4,5-bis(4-methoxyphenyl)-5H-chromeno[4,3-b]pyridin-2-yl)- phenol (C32H25NO4, Mr = 487.53) was synthesized and crystallized. The crystal belongs to monoclinic, space group P2(1)/c with a = 12.4170 (11), b = 18.313 (2), c = 11.7103 (10) ?, β = 111.569(2)°, V = 2476.4(4) ?3, Mr = 487.53, Z = 4, Dc = 1.308 g/cm3, μ(MoK α ) = 0.086 mm−1, F(000) = 1024, the final R 1 = 0.0632 and wR 2 = 0.1454. X-ray analysis reveals that the atoms of C(1), C(2), C(3), C(4), C(5) and N(1) form a planar six-membered ring, while the atoms of C(1), C(2), C(6), C(7), C(12) and O(1) form a six-membered ring of envelope conformation. 相似文献19.
Wesley H. Monillas Glenn P. A. Yap Klaus H. Theopold 《Journal of chemical crystallography》2009,39(11):842-845
Abstract
The complexes (TMEDA)Cr(I)2(THF) (1) and [(N,N-DMEDA)2CrI] I (2) were synthesized and spectroscopically characterized (TMEDA = tetramethylethylenediamine, N,N-DMEDA = N,N dimethylethylenediamine). Complex 1 possesses square pyramidal geometry and crystallizes in spacegroup Pbca with crystal cell parameters a = 11.206(2) ?, b = 12.698(3) ?, c = 23.434(5) ?, V = 3,334.6(12) ?3 and Z = 4. Complex 2 also possesses square pyramidal geometry with a non-coordinated iodide counter anion and crystallizes in spacegroup P21/n with crystal cell parameters a = 9.4071(13) ?, b = 14.628(2) ?, c = 11.7516(16) ?, β = 98.904(2) ?°, V = 1,597.6(4) ?3 and Z = 4. Complex 2 has previously been incorrectly assigned as an octahedral complex based on spectroscopy. 相似文献20.
Carolina Escobedo-Martínez María Concepción Lozada Raúl G. Enríquez Manuel Soriano-García William F. Reynolds 《Journal of chemical crystallography》2010,40(3):241-247