【摘要】 本文报道了一种钒、钨异金属八核簇合物[VW₃O₄（O₂CEt）₈]₂Na₂（1）在恒温液相条件下的合成与结构研究.晶体属三斜晶系,P（?）空间群,a=1.2973（4）,b=1.4063（3）,c=1.2396（5）nm,α=109.92（2）,β=117.33（2）,γ=90.53（2）°,V=1.8513nm³,D_c=2.29g/cm³,Z=1,对5499个可观测反射点[I>3σ（I）]最终一致性因子为R=0.030.单晶结构分析表明,簇阴离子中两个[W₃O₄]⁴⁺单元通过两个“桥”金属V原子连接成一个奇特的环状结构.W—W平均键长为0.25328（6）nm,W…V间平均距离为0.3654nm.簇阴离子通过Na⁺连成一个一维长链.Na原子具有少见的五配位,Na—O距离仅为0.2314nm.Na—O间较强的相互作用以及无限长链的晶体结构很好地解释了簇合物I的稳定性和不溶性.更多还原

【Abstract】 The insoluble octanuclear mixed-metal cluster [VW3O4(O2CEt)8]2Na2 (1) has been prepared by the redox reaction of W(CO)6 with NaVO3in propionic anhydride. The crystal is triclinic of space group P1 with a =1.2973(4), b=1.4063(3), c= 1.2396(5)nm, α =109.92(2), β=117.33(2), γ = 90.53(2)°, V=1.8513nm3,Dc = 2.29g/ cm3, Z= 1, final R= 0.030 for 5499 observed reflections [I>3σ(I)]. It is shown that the structure of the compound consists of an interesting centrosymmetric anion, where two [W3O4]4+ units are connected by two V atoms to complete a circular specie. The averaged W-W bond lengths are 0.25328(6)nm and the averaged distance between V and W atoms are 0.3654nm. The anions are connected by Na+ to form a one-dimensional infinite chain structure. Each Na atom is coordinated to five oxygen atoms with average Na-O distance of 0.2314nm. The short Na-O distance and chain structure are responsible for the insolubility of the cluster 1.更多还原