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王肖君  竺Nai珏 《结构化学》1991,10(2):103-105
<正> The title compound C11H12NzO,Mr= 188. 25. Crystalizes in monoclinic space group P21/n with the following cell parameters;a= 7. 108(4),b= 6. 371(3),c = 21.588(11)A,β=97. 32(2)°. V = 969. 7(8)A3,Z=4,Dc=1. 29g/cm,μ(MoKa) = 0. 9cm-1,F(000) = 400. The final R=0. 068 for 1046 independent reflections with F≥2. 5σ(F). The molecule exists in ketene aminal form rather than in its imine or enol form.  相似文献   

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谌了容  喻宗沅 《结构化学》1992,11(2):118-121
<正> C18H18O6·H2O, Mr = 348. 34, cis-isomer: orthorhombic, Cmc21, a = 16. 421(3), 6 = 11.978(1), c=8. 624(1)(?), V = 1696. 2(?)3, Z = 4, Dc= 1.293 gcm-3, λ(MoKα) = 0. 71073(?), μ = 0. 911cm-1, F (000) = 763, R = 0. 043, Rw = 0. 042 for 769 unique observed reflections. trans-Isomer : orthorhombic, Cmc21, a = 16. 503(2), b = 12. 297(2), c=8. 557(3) (?). V = 1736(?)3, Z = 4, Dc= 1.271 gem-3, λ(MoKα) = 0. 71073(?), μ = 0. 892cm-1, F (000) = 736, R=0.048, Rw = 0. 046 for 551 unique observed reflections. The configurations of the two molecules appear as butterflies. There is a Cm symmetry in the molecule of each isomer.  相似文献   

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魏国卫  黄致盈 《结构化学》1991,10(2):159-161
<正> Anaerobic reaction of Pt (dppe)Cl2 (dppe = Ph2PCH2CH2PPh2) with NaSPh and elemental selenium affords complex Pt(dppe)(SPh)2,which crystallizes in the monoclinic system space group C2/c with a=14. 392(7) ,b=16. 380(7) ,c=14. 266(5) A ,β=86. 44(4)°,V=3342(5) A3,Z = 4,Dc=1. 613g/cm3,and μ(MoKa) = 44. 813 cm-1. The final structural refinement converged with unweighted and weighted R factors of 0. 041 and 0. 057 for 2206 observed reflections (I>3σ(I)). X-ray analysis shows that the Pt atom in Pt(dppe)(SPh)2 is at the center of the approximately planar tetragon of two P atoms and two S atoms.  相似文献   

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We have determined the crystal structure of Al-(D-Trp) insulin and discovered that it belongs to the trigonal system with space group R3. The parameters of the unit cell are a=b=78.6, c=50.0. A set of data for half a sphere reciprocal space to a spacing of 2.2 were collected. The model was adjusted and refined by using a step-by-step approach and a stereochemically-restrained least squares program, assisted by manual revision based on the difference Fourier maps, to a final R-factor of 0.218. The main and side chains of both Al-D-Trp residues in the asymmetric unit are well ordered. The packing of Al-(D-Trp) insulin in the unit cell, the conformational differences with other insulin structures and its structure and function relationship bave also been discussed.  相似文献   

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刘扬  刘秀华 《结构化学》1990,9(2):87-89
<正> C11H13 N3 O5·t-Bu- N = CHC6H3(NO2)2,Mr = 267. 27, Monoclinic space group C2/c,a= 18. 546(3),b = 5. 729(1),c= 27. 479(5) A,β= 118. 42(1)°/,F = 2567. 6(9)A3,F(000) = 1120,Z=8,Dx=1. 38g/cm3. The structure of DNPBN is akin to that of PBN reported by us except for shorter N - O and C = N bonds.  相似文献   

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标题化合物(Ⅰ)经由Mo_4S_4(μ-dtp)_4(Ⅱ)[dtp=S_2P(OEt)_2]和Ni(OAc)_2反应而得。(Ⅰ)晶体属单斜晶系,空间群P2/c,a=13.176(4),b=11.699(3),c=18.526(4)(?),β=116.11(3)°,V=2564(3)(?)~3,Z=2,D_c=1.776g·cm~(-3)。晶体结构由直接法解出,最终偏离因子R=0.085。本文结果表明,可由已知的四核钼簇合物经过配体置换反应,合成得到其簇骼中心[Mo_4S_4]保持不变并具有-OAc作为桥式配体和-dtp作为端基配体的混合配体类立方烷[Mo_4S_4]簇合物。  相似文献   

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<正> BaGa4,tetragonal space group I4/mmm with lattice parameters a=b=4.5650(8), c=10.786(2)A, V=224.77(7)A3,Dc=6.15 gcm-3,and Z=2,λ(MoKα)=0.71069A,μ=335.93cm-1,F(OOO) =360. The final R = 0.045, Rw=0.069.The distribution of valence electrons in crystal Ba6a4 is described and a suggestion that two different types of gallium atoms form covalent bonds by utilizing sp3 and dsp3 hybrid orbitals respectively is proposed.  相似文献   

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何亦宗  黄小荥 《结构化学》1993,12(5):346-349
<正> Title compound Na5Y (WO4)4 (Mr = 1195. 24) crystallizes in the space group I41/a with the cell parameters a= 11. 447(7), c= 11. 336(1) A , Z = 4, V = 1485(2) A3, A = 5. 34 g/cm3. A(MoKα) = 0. 71069 A. F(000) = 2702, final R = 0. 045,Rw = 0. 054 for 936 observed reflections with I≥3σ(I). The title compound has a scheelite structure.In this paper, we also give the X-ray powder diffraction data of Na5Y(WO4)4 obtained by using a D/max-ra type diffractometer.  相似文献   

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<正> PRELIMINARY INFORMATION. The title compound is a member of a series of cobalt complexes of polydentate ligands currently being investigated. It was prepared by the reaction of CoSO_4·7H_2O with phenanthroline in the equimolar ratio.  相似文献   

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<正> The effect of structure on the defective formation in non-linear optical crystal of lithium boric oxide(LBO)was studied by X-ray topography.Only a few dislocations with the density less than 50/cm2 occur in the specimen cut far from the seed.Most inclusive formed in the late growth stage show a regular orthorhombic shape with a definite orientation,which are due to the negative crystal growth happened further in the inclusioned melt.The grown-in dislocation takes nearly the screw character with the Burgers vector b almost all in the low index directions,however,the inclusion-induced dislocation is distributed much closely in a network parallel only to the plane of(010)and also takes the screw type with b all in the lowest diretions of this plane.The high movability of lithium ions in open structure and the loosely atmic packings on certain planes were taken into account for the defect formation in addition to for some other crystal properties.  相似文献   

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用SYNTEXP3/R3四圆衍射仪收集4-(2-吡啶偶氮)间苯二酚盐酸盐晶体的三维衍射数据。晶体属P21/c空间群,a=11.339Å,b=6.835Å,c=18.170Å,β=102.76°,Z=4。利用Patterson法及直接法测定了晶体结构。经位置坐标参数,各向异性温度因子及比例因子块矩阵最小二乘修正后,最后的R值为0.055。晶体结构分析结果表明:4-(2-吡啶偶氮)间苯二酚的分子内所有非氢原子共面并形成大的共轭体系。氯离子及二个结晶水与分子中的N,O形成氢键,起到桥联分子的作用。  相似文献   

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