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无水FeCl_3和格氏试剂在THF中反应,反应产物在DMF中重结晶,得到(Mg·6DMF)[(FeCl_3)_2O]的晶体,在NMF中重结晶,得到FeCl_3·3NMF。本文讨论了氧桥生成的条件。(Mg·6DMF)((FeCl_3)_2O]和(Et_4N)_2[MoFeS_4Cl_ 2)在DMSO中反应得到一非化学计量的笼状化合物,其分子式为[MoFeS_4Cl_2]。[Fe_2S_2Cl_4]_(1-a)(Fe·6DMSO)_b(Mg·6DMSO)_(1-b。) 分别测定了(Mg·6DMF)((FeCl_3)_2O]及其衍生物的晶体结构。首次发现了单氧桥二铁化合物的交错型四配位直线氧桥结构,它存在于(Mg·6DMF)~(2+)的笼状母体中。 (Fe·6DMSO)~(2+)统计分布于(Mg·6DMSO)~(2+)的笼状骨架上,而阴离子[MoFeS_4Cl_2]~(2-)和[Fe_2S_2Cl_4]~(2_)统计分布在这个笼状母体中。 在FeCl_3·3NMF中,可以看到Fe—Cl键的对位效应。 相似文献
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The synthesis and crystal structure of two trinuclear molybdenum clusters containing a loosecoordination site, {Mo_3(μ_3-S)(μ-S)_3[S_2P(OEt)_2]_4(C_3H_3ON)}· CH_3CN (Ⅰ) and {Mo_3(μ_3- O)-(μ- S)_3[S_2P(OEt)_2]_4(C_3H_3ON)} (Ⅱ), are reported. Cluster (Ⅰ) belongs to the monoclinic spacegroup p2_1/n, a = 16.579 (3), b = 16.959 (2), c = 16.867 (2) A, β= 94.44 (1)°, V = 4728A~3,Z = 4, D_c = 1.778g·cm~(-3). The crystal structure was solved by the Patterson method with afina1 R value of 0.045. Cluster (Ⅱ) belongs to the triclinic space group Pi, a = 13.175 (4),b = 13.372(6), c = 16.656(3)A, α= 117.87(4), β= 60.09(3), γ= 109.03(3)°, ν= 2231A~3,Z = 2, D_3 = 1.798g·cm~(-3). Direct methods were used to solve the crystal structure with afinal R value of 0.066. Both clusters are monocapped trinuclear ones having an oxazoleoccupied coordination site as their main structural characteristic. The difference in cappingatoms results in the difference in their skeletons, Mo_S_4 in cluster (Ⅰ) vs. Mo_3OS_3 相似文献
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The title crystal belongs to the monoclinic system. The space group is P2_1/c with unit cell parameters: a=11.379(3), b=20.766(2), c=14.487(3), β=91.49(2)°, V=3519(2)~3Z=4, D_c=1.819g.cm~(-3), D_0=1.81g.cm~(-3). The crystal structure was solved by the heavy atom method and difference Fourier synthesis and refined by the full-matrix least-squares to a final R factor of 0.040 based on 3261 unique reflections with intensities I≥3σ(I). The structure consists of two sots of tetraethylammonium cations and trinuclear Me cluster anions. In the cluster anion the three Mo atoms form an isosceles triangle with Mo-Mo distances of 2.601(1), 2.608(1), 2.642(1), respectively, showing a strong bonding interaction between the metal atoms. One μ_3-O atom and one μ_3-Cl atom are situated above and below the triangle respectively, binding the three Me atoms to form a triangular bipyramidal cluster core. Each pair of Mo atoms is bridged further by a μ_2-Cl atom situated on the Mo_3 triangular plane. In addition, each 相似文献
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[Mo_5P_2O_(23)]~(6-)[(CH_3)_2NH_2]_5~(5+)[H_3O]~+·1/2DMF·1/2H_2O(DMF=(CH_3)_2NC-HO)(M_r=1204.67)的晶体属三斜晶系,空间群P,晶胞参数a=16.438(6);b=22.22(1);c=11.325(5),α=104.25(4);β=108.97(3);γ=97.68(4)°,V=3688(3),Z=4,D_c=2.17gcm~(-1),R=0.056,R_w=0.074,晶胞中每个不对称单元含有两个[Mo_5P_2O_(23)]~(6-)[(CH_3)_2NH_2]_5~(5+)[H_3O]~+·1/2DMF·1/2H_2O,阴离子[Mo_5P_2O_(23)]~(6-)中的Mo、P原子成一个畸变五角双锥构型。有一个阴离子的所有原子(Mo、P、O)位置完全确定,而另一个阴离子有一个磷酸根的三个氧原子位置出现二重位置统计分布。化合物的阳离子为二甲胺阳离子和水合氢离子。 相似文献
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本文报道了具有局部松散配位的三核钼原子簇{Mo_3(μ_3-S)(μ-S)_3[S_2P(OEt)_2]_4·P(C_6H_5)_3}·(0.86CH_2Cl_2)的合成和晶体结构。晶体属三斜晶系,空间群为PI,单胞参数a=10.472(4),b=14.375(2),c=21.695(3)A;α=74.04(1),β=76.50(2),γ=72.22(2)°,V=2950A~3,D_c=1.693g·cm~(-3),Z=2.在CAD-4四圆衍射仪上用MoKα射线收集到I≥2σ(Ⅰ)的衍射点4840个。采用重原子法和差电子密度法解出结构,并用全矩阵最小二乘法修正,最终偏离因子为0.058。簇分子的Mo-Mo键为2.731(1),2.748(1),2.753(1)A,Mo原子和三苯基膦的P原子配位键长为Mo-P2.647(3)A,显著长于一般的Mo-P共价单键。三苯基膦基团在Mo的配位多面体中处于三重桥S原子的对位,表现出与其他此类簇合物的松散配位体配位位置不同。文中概括了此类簇合物的Mo—Mo键和Mo-L的成键情况。 相似文献
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中国化学会是适应社会历史和科学技术发展而产生的群众性学术团体,其主要任务在于团结广大化学工作者,开展学术交流,积极促进和推动科学技术的发展。在灾难深重的旧中国,四十五名爱国的化学工作者为共图化学在中国的发展和应用,1932年8月在南京发起组建了中国化学会。这五十年的历程尽管艰难、曲 相似文献