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151.
NG Seik  Weng 《结构化学》2011,30(9):1286-1288
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.  相似文献   
152.
《结构化学》2013,(1):154
<正>《结构化学》是由中国科学院主管,中国化学会、中国科学院福建物质结构研究所主办的学术性期刊。1982年由我国著名化学家卢嘉锡院士创办并担任主编,现任主编是著名化学家吴新涛院士。《结构化学》主要报道晶体学,量子化学,药物、材料和催化剂等领  相似文献   
153.
MCRs for preparation of chromenopyridines under reflux conditions and chromenes at room temperature conditions from different salicylaldehydes,malononitrile and different thiols(mol ratio- 1:2:1) were established.Mechanistic investigation suggests that the MCRs undergo different pathways at different temperatures and catalyzed by different organic bases.The structure of chromenopyridine and chromene are confirmed by crystal X-ray crystallography.  相似文献   
154.
《物理》2012,(1):57-59
现代晶体学(第1卷)晶体学基础:对称性和结构晶体学方法(第2卷)晶体的结构出版社:中国科学技术大学出版社作者:[俄]B·K·伐因斯坦等开本:16开页码:432(第1卷)/472(第2卷)定价:60元/卷购书电话:0551-3607216内容简介:《现代晶体学》由4卷组成,原著俄文版和英文版近乎同时出版,出版后曾在整个学术界引起了极大反响.该书是著名晶体学家B·K·伐因斯坦主编的晶体学经  相似文献   
155.
《光谱实验室》2012,(3):1392
(你的论文在发表后约1-2个月,上网才能检索到)1.在浏览器的地址栏上输入"中文核心期刊"。当出现菜单后,点击"2011年中文核心期刊目录",即可查阅各学科的"核心期刊"。若要查阅《光谱实验室》,请查第4编:自然科学,再查"O6/O7—化学/晶体学",第21  相似文献   
156.
赵恒武  李斌 《结构化学》2012,31(1):61-66
Hydrothermal reactions between a new flexible multicarboxylate ligand of 3-(2-carboxy-phenoxy)-benzoic acid(H2L) and transitional metal cations of M2+(M = Cu2+,Ni2+) in the presence of the secondary ligands of 1,10-phenanthroline(phen),2,2'-bipyridine(2,2?-bpy),and 4,4'-bipyridine(4,4'-bpy) afford two novel coordination polymers Ni2(H2O)2L2(phen)(μ-4,4'-bpy)(1) and CuIIL(2,2'-bpy)(2).Both compounds were characterized by X-ray crystallography.Crystal data of 1:C31H24N3NiO7,Mr = 609.24,monoclinic,space group P21/c,a = 17.560(8),b = 10.528(5),c = 30.613(15) ,V = 5659(5) 3,Z = 4,Dc = 1.430 g/cm3,F(000) = 502,μ = 0.739 mm-1,R = 0.0902,wR = 0.1346(I > 2σ(I)),S = 1.002.Crystal data of 2:C24H16CuN2O5,Mr = 475.93,monoclinic,space group P21/n,a = 9.8904(13),b = 11.0782(16),c = 18.321(3) ,β = 11.0782(16)°,V = 1993.8(5) 3,Z = 4,Dc = 1.585 g/cm3,F(000) = 972,μ = 1.137 mm-1,R = 0.0433,wR = 0.0723(I > 2σ(I)) and S = 1.004.Compound 1 displays a one-dimensional(1D) zigzag chain structure constructed from phen ligands and the deprotonated ligands of L2-,which further forms a ladder-shaped supramolecular architecture via the bridge of 4,4'-bpy ligand.Complex 2 also possesses a ladder-shaped architecture based on the dinuclear CuII units.  相似文献   
157.
A new copper(II)-2,2'-biimidazole metal-organic POMs-supported compound [Cu(H2biim)2]{[Cu(H2biim)212[H10W12O44]}'8H2O (H2biim = 2,2'-biimidazole) has been success- fully synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, IR spectroscopy, elemental analysis and TG. The crystal adopts space group Pi with a = 11.800(2), b = 13.437(3), c = 13.685(3) A, V = 1922.5(7) A3, D,. = 3.507 g/cm3, C36H62Cu3N24W12O52, M,. = 4059.92, F(000) = 1837,μ = 18.796 mm-1, Z = 1, R = 0.0579 and wR = 0.1465 for 8734 observed reflections (I 〉 2σ(I)). X-ray crystallography analysis exhibits that the title compound consists of one [H10W12044]6- polyanion and three [Cu(H2biim)2] units. And significant π-π stacking interactions and intermolecular O-H-,.O or N-H.'-O hydrogen-bonding interactions lead to a three-dimensional supramolecular framework. Thermal stability and magnetic property of the complex have also been investigated.  相似文献   
158.
原点规定除P1空间群外,所有非中心对称空间群都有特殊和一般两种反射。习惯上总是用或尽可能用特殊反射的位相给值规定允许原点。而目前的直接法都是用已知位相的线性组合个别推导位相。所以作为起始套组成部分的原点定义反射应该是|E|值大而且参与线性组合次数  相似文献   
159.
To evaluate the effect of neutral C–H bond or electron pair of nitrogen atom with sp2hybridization(N(sp2)) involving into the same chemical environment for anion binding, two analogous tetracationic imidazolium macrocycles, namely cyclo[2](2,6-bis-(1H-imidazol-1-yl)pyridine) [2](1,3-dimethylenebenzene)(14+), and cyclo[2](2,6-bis-(1H-imidazol-1-yl)pyridine)[2](2,6-di methylenepyridine)(24+)were studied in detail as small inorganic anion receptors. The guest anions with different shapes are Cl,N3, NO3, and H2PO4. The host–guest interactions were characterized via1 H NMR spectroscopy,electrospray ionization mass spectrometry(ESI-MS) and single crystal X-ray crystallography. The results implied that macrocyclic hosts with similar backbone but two distinct binding sites(14+with neutral C–H vs. 24+with N(sp2)) vary markedly in their response to anions, including the binding modes and association constants. The finding will serve to the construction of new anion receptors, even improve insights into the anion binding process in biology.  相似文献   
160.
序言     
<正>庆祝唐有祺教授九十寿辰暨执教六十年本期《物理化学学报》是庆祝中国科学院院士、北京大学化学与分子工程院教授、物理化学学报主编唐有祺教授九十寿辰暨执教六十年的特刊。特刊所收集的文章主要来自于唐有祺教  相似文献   
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