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Indexing Non-merohedrally Twinned Crystals by Bruker'sAPEX2 and Agilent's CrysAlis^(PRO), an Example of a Crystal Structure That Can Be Refined through Either the PLATONRoute or the ‘HKLF 5' Route, and, Simultaneous Data Collection of Two Crystals in a Tw 被引量:2
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作者 ng seik weng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第2期294-303,共10页
The first part of this report describes the data reduction of non-merohedrally twinned crystals measured on Bruker and Agilent area-detector diffractometers. The image frames of methyl-2-aminopyrazine-3-carboxylate we... The first part of this report describes the data reduction of non-merohedrally twinned crystals measured on Bruker and Agilent area-detector diffractometers. The image frames of methyl-2-aminopyrazine-3-carboxylate were processed with APEX2 to furnish a set of overlapping diffraction indices that were used for solution and refinement. CrysAlisPRO was used for processing the frames of bis(diethyldicarbamato)nickel, which exists in monoclinic and tetragonal polymorphs, and in untwinned and twinned forms. In the second part, the crystal structure of [(3-formyl-4- hydroxyphenyl)methyl]triphenylphosphanium chloride was refined through the ‘HKLF 5'(based on a combined set of diffraction indices) and PLATON(based on one set of diffraction indices) routes to give identical outcomes because the amount of overlap of the twin domains is small. For the third part, in a proof-of-concept investigation, the diffraction pattern of untwinned and twinned 4-{(E)-(4-aminophenyl)diazenyl]phenylamine was recorded simultaneously in one run; the three domains could be indexed and the crystal structure satisfactorily refined. The refinement was identical to those derived from independent measurements; the crystal structure features two independent centrosymmetric molecules, one of which is ordered and the other whole-molecule-disordered. This two-in-one run opens up the possibility that two or more crystals having different atomic compositions can be measured simultaneously if their reciprocal lattices do not overlap significantly. 展开更多
关键词 merohedral non-merohedral twin APEX2 Crys Alis^PRO two-in-one data collection
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GS型包合物G_2PEDS·MeOH·2(H_2O)和G_2PEDS·naphthalene的合成与晶体结构
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作者 廖成竹 蔡继文 +1 位作者 冯小龙 ng seik weng 《有机化学》 SCIE CAS CSCD 北大核心 2002年第11期889-893,共5页
合成了两个由胍盐 (G)和 4 ,4′ 苯醚二磺酸 (PEDS)为主体框架所形成的主 -客体包合物 ,分别为 [(CH6 N3) ]2[(C1 2 H8O7S2 ) ]·MeOH·2 (H2 O) (1)和 [(CH6 N3) ]2 [(C1 2 H8O7S2 ) ]·(C1 0 H8) (2 ) .两个化合物都是以... 合成了两个由胍盐 (G)和 4 ,4′ 苯醚二磺酸 (PEDS)为主体框架所形成的主 -客体包合物 ,分别为 [(CH6 N3) ]2[(C1 2 H8O7S2 ) ]·MeOH·2 (H2 O) (1)和 [(CH6 N3) ]2 [(C1 2 H8O7S2 ) ]·(C1 0 H8) (2 ) .两个化合物都是以P 1空间群结晶 ,晶胞参数分别为 :1a =0 75 0 9(4)nm ,b =1 2 113(6 )nm ,c =1 5 936 (8)nm ,α =10 2 6 36 (10 )°,β =10 2 70 3(11)° ,γ =91 318(10 )°;2a =0 75 4 0 9(3)nm ,b =1 2 15 84 (5 )nm ,c =3 0 9376 (14 )nm ,α =81 5 0 6 (2 )°,β =89 6 6 9(2 )°,γ =88 890 (2 )° .在这两个晶体结构中 ,G和PEDS通过氢键形成了双夹层 -双柱子的主体框架 ,客体分子被包合在平行于a轴方向的晶格空间 .这种双夹层 -双柱子的主体框架在由胍盐 (G)和有机二磺酸 (S)体系所形成的。 展开更多
关键词 胍盐 4 4’-苯醚二磺酸 主—客体化合物 构筑异构体 GS型包合物 G2PEDS·MeOH·2(H2O) G2PEDS·naphthaEene 晶体结构
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Crystal Structure of catena-[(Tetrakis-μ_2-acetato-μ_2-4,4'-bipyridine) dicopper(Ⅱ)] Acetonitrile Solvate 被引量:1
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作者 温一航 何银华 +1 位作者 冯云龙 ng seik weng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第1期29-32,共4页
The title compound, [Cu2(CH3COO)4(C8H10N2)]n·nCH3CN 1 (C8H10N2, 4,4'-bipy = 4,4'-bipyridine), has been solvothermally synthesized in CH3CN and characterized by X-ray diffraction. The crystal is of monocli... The title compound, [Cu2(CH3COO)4(C8H10N2)]n·nCH3CN 1 (C8H10N2, 4,4'-bipy = 4,4'-bipyridine), has been solvothermally synthesized in CH3CN and characterized by X-ray diffraction. The crystal is of monoclinic, space group Cc with α = 22.626(6), b = 14.012(4), c = 15.106(4) ]A, β = 107.610(3)°, V = 4565(2) ]A^3, C20H23Cu2N3O8, Mr = 560.49, Z = 8, Dc = 1.631 g/cm^3,μ = 1.914 mm^-1, Flack parameter = 0.48(1), F(000) = 2288, R = 0.042 and wR = 0.098 for 8887 observed reflections (I 〉 20(I)). It consists of nearly linear one-dimensional chains [Cu2(CH3COO)4(C8H10N2)]n derived from paddle-wheel [Cu2(CH3COO)4] unit linked by 4,4'-bipy, and CH3CN as guest molecule regularly decorates between the chains. 展开更多
关键词 Cu complex paddle-wheel unit crystal strueture guest molecule
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On the Crystal Structure of [Cu(OH)_2(H_2O)_2(4-C_5H_4NCOOH)_2] 被引量:1
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作者 ng seik weng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第4期495-495,共1页
The compound described as [Cu(OH)2(H2O)2(4-C5H4NCOOH)2] in Chin. J. Struct. Chem., 2001, 20: 478-480 is instead the compound [Cu(H2O)4(4-C5H4NCOO)2], whose crystal structure has already been published elsewhere.
关键词 C5H4NCOOH H2O CU On the Crystal Structure of
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Non-merohedrally Twinned Crystal Structure of the Co-crystal Ethyl 6-(2-5-(Ethoxycarbonyl)-pyridin-2-yl-1,2-dihydroxyethyl)pyridine-3-carb-oxylateethyl 6-(2-5-(Ethoxycarbonyl)pyridin-2-yl-2-hydroxyacetyl)pyridine-3-carboxylate(0.69/0.31) 被引量:1
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作者 ZHAng Wen-Hua ng seik weng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第8期1159-1162,共4页
The two component molecules of the co-crystal 0.69(C18H2ON206).0.31(C18H18N2O6) lie on a center-of-inversion that exists midway along the ethylene chain connecting the two aromatic rings. The two molecules are sup... The two component molecules of the co-crystal 0.69(C18H2ON206).0.31(C18H18N2O6) lie on a center-of-inversion that exists midway along the ethylene chain connecting the two aromatic rings. The two molecules are superimposed. The crystal is also a non-morohedral twin with a minor 37.7(2)% component. The refinement of this twinned and disordered crystal structure is detailed. Crystal data: C18H19.38N2O6, monoclinic, P21/c, a = 17.1687(8), b = 5.4389(2), c = 9.3261(4) A, b = 95.270(5)° and V= 867.18(6) A3 at -173 ℃. 展开更多
关键词 CO-CRYSTAL non-merohedral twin
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Space Group of Aquaimidazolemaleatozinc, [(H_2O)(C_3H_4N_2)(O_2CCH=CHCO_2Zn)]_n
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作者 ng seik weng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第1期121-121,共1页
The space group of [(H2O)(C3H4N2)(O2CCH=CHCO2Zn)]n, which was originally described in the acentric Pc space group (Liu et al., Chin. J. Struct. Chem. 2004, 23, 160~163), is re-described in the centric P21/c space g... The space group of [(H2O)(C3H4N2)(O2CCH=CHCO2Zn)]n, which was originally described in the acentric Pc space group (Liu et al., Chin. J. Struct. Chem. 2004, 23, 160~163), is re-described in the centric P21/c space group. 展开更多
关键词 CCH O2CCH=CHCO2Zn Space Group of Aquaimidazolemaleatozinc O2CCH C3H4N2 H2O
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‘Whole-molecule Disorder’ Refinement of 4-(4-Hydroxybenzylideneiminio)phenol Hemichloride Hemihydroxide
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作者 ng seik weng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第9期1283-1285,共3页
The two independent cations of the salt, [HO-C6H4-CH=NH-C6H4-OH]·1/2OH·1/2Cl, are both disordered about an axis connecting the two oxygen atoms at the para-positions of the aromatic rings, the disorder being... The two independent cations of the salt, [HO-C6H4-CH=NH-C6H4-OH]·1/2OH·1/2Cl, are both disordered about an axis connecting the two oxygen atoms at the para-positions of the aromatic rings, the disorder being in a 83:17 ratio in one cation and 91:9 in the other. The hydroxide and chloride anions are ordered. The treatment of the nearly ‘whole-molecule disorder’ by employing a small number of restraints is described. Crystal data: C13H12.5Cl0.5NO2.5, triclinic, P , a = 9.1731(4), b = 9.2048(4), c = 15.9144(7) , α = 104.822(1), β = 90.077(1), γ = 118.641(1)o and V = 1127.86(9) 3 at –173 K. 展开更多
关键词 whole-molecule disorder
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‘Whole-molecule Disorder’ Refinement of 4-Tricyanovinyl-N,N-diethylaniline
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作者 ng seik weng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第9期1286-1288,共3页
The molecule of 4-tricyanovinyl-N,N-diethylaniline is disordered about an axis that is close to the axis passing through the 1,4-carbon atoms. The disorder is a 1:1 type of disorder that involves only part of the mol... The molecule of 4-tricyanovinyl-N,N-diethylaniline is disordered about an axis that is close to the axis passing through the 1,4-carbon atoms. The disorder is a 1:1 type of disorder that involves only part of the molecule as the diethylamino substitutent and the three nitrogen atoms of the tricyanovinyl substituent are ordered. The treatment of the nearly ‘whole-molecule disorder’ by employing a small number of restraints is described. Crystal data: C15H14N4, triclinic, P , a = 7.1996(5), b = 7.7232(5), c = 12.4171(8) , α = 99.350(1), β = 94.647(1), γ = 103.312(1)o and V = 657.90(8) 3 at –173 K. 展开更多
关键词 whole-molecule disorder
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On Chiral Space Groups and Chiral Molecules
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作者 ng seik weng 胡盛志 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第1期37-38,共2页
This note explains the relationship (as well as the absence of a relationship) between chiral space groups and chiral molecules (which have absolute configurations). For a chiral molecule, which must crystallize in a ... This note explains the relationship (as well as the absence of a relationship) between chiral space groups and chiral molecules (which have absolute configurations). For a chiral molecule, which must crystallize in a chiral space group, the outcome of the absolute configuration determination must be linked to some other properties of the chiral crystal such as its optical activity for the observation to the relevant. 展开更多
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6-四氮唑-2-吡啶甲酸配合物的原位合成与氢键拓扑网络研究 被引量:2
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作者 杨英宜 詹顺泽 +2 位作者 李冕 李丹 ng seik weng 《中国科学:化学》 CAS CSCD 北大核心 2013年第10期1297-1308,共12页
用2,6-二氰基吡啶与叠氮化钠在水热条件下原位合成了5种6一四氮唑.2-吡啶甲酸配合物:【Ni2(tepc)2(H2O)2】(1),[CO2(tepc)2(H2O)4]·2H2O(2),【CO2(tepc)2(H2O)4】·4H2O(3),【Cu2(tepc)2(H2O)2](... 用2,6-二氰基吡啶与叠氮化钠在水热条件下原位合成了5种6一四氮唑.2-吡啶甲酸配合物:【Ni2(tepc)2(H2O)2】(1),[CO2(tepc)2(H2O)4]·2H2O(2),【CO2(tepc)2(H2O)4】·4H2O(3),【Cu2(tepc)2(H2O)2](4)和{【Mn(tepc)(H20)2]·2H2O}n(5)(tepc=6一(tetrazol-5-y1)picolinate).这些配合物中配体均以三齿螯合的方式与金属离子配位.配合物1-4形成了双核离散型配合物,双核分子通过氢键作用连接成三维超分子结构.配合物5中的单核螯合单元间通过Mn-O配位键连接成为一维配位聚合物链,链间通过氢键连接成为整个配合物的晶体结构.氢键拓扑网络分析表明,配合物1和2可简化成NaCI型的6-连接pcu拓扑网,配合物3则可简化成一种8.连接hex拓扑网,配合物4可简化成一种新型双结点十连接拓扑网络(3^10.4^26·5^8·6)(3^8.4^26.5^10.6),配合物5则可简化成一种新型的(5,10)双结点三维网络(3^2·4^7.5)(3^4.4^21.5^13.6^7).本文不仅详细地分析了这些配合物晶体结构中氢键与拓扑网络之间的关系,而且还讨论了氰基的水解反应与四氮唑成环反应间的关系,以及金属离子的电子特征、结晶条件与晶体结构之间的关系. 展开更多
关键词 原位合成 四氮唑 氢键 拓扑分析
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