一些Ag+、Cu+簇的合成和结构研究

由于银,铜簇合物有助于催化理论的研究,近20年来,许多学者对它们的合成方法、成簇规律和结构特点进行了许多探索。本文报道了[Me_4N]_6[Ag_6[S_2C=C(CN)_2)_6]·H_2O(Ⅰ)、[Et_4N]_4[Cu_8(S_2C=C(CN)_2)_6](Ⅱ)和[Me_4N]_4[Cu_5Ag_3(S_2C=C(CN)_2)_6]·H_2O(Ⅲ)的化学合成,化合物(Ⅰ)和(Ⅱ)的晶体和分子结构,以及从化合物(Ⅲ)的ICP元素分析和红外光谱分析,探讨它的结构特征。

THE SYNTHESIS AND CRYSTAL STRUCTURES OF Ag+ Cu+ CLUSTER COMPOUNDS

(Me_4N)_6 (Ag_6(S_2C=C(CN)_2)_6) H_2O(Ⅰ), (Et_4N)_4 (Cu_8(S_2C=C(CN)_2)_6)(Ⅱ) and (Me_N)_4(Cu_5Ag_3(S_2C=(CN)_2)_6H_2O (Ⅲ) were synthesized. The crystal and molecular structures of the compounds (Ⅰ) and (Ⅱ) were determined with single crystal x-ray diffraction method, crystal data: complex (Ⅰ), trigonal, space group R3, hexagonal cell dimensions, a=b=2.38358, c=1.16716 nm, v=574.28 nm~3, Mr=1951.23, z=3, D_c=1.693 g cm~(-3), final R=0.044 for 3648 independent reflections with Ⅰ≥3σ(Ⅰ); Complex(Ⅱ), monclinic, space group P2_1/n, a=1.47243, b=1.72275, c=1.55944 nm, β=100.75°, v=388.63 nm~3, Mr=1870.46, z=2, D_c=1.598 gcm~(-3), final R=0.061 for 3890 independent reflections with I≥3δ(I). The molecular symmetry of complex (I) is 3, contaioning an Ag_6S_(12) core. six Ag atoms form two centrosymetrically related equilateral triangles antiprism, with the Ag-Ag distances of 0.3610(1) nm, Each Ag atom is bounded two nearest neighbour Ag atoms of other equilateral triangle to form a isosceles triangle with two Ag-Ag distances of 0.3127(1) nm. The molecular symmetry of complex (II) is Ci, containing a Cu_8S_(12) core, eight coper atoms form a distorted cubic, with the Cu-Cu distances of 0.2755(1)-0.2872 nm. The complex (III) have been characterized by ICP elemental analyses and IR spectra, the Cu_5Ag_3S_(12) core of complex (III) is probably similar to the Cu_8S_(12) core of complex (II).