CO_xM_(4—x)异金属四面体簇羰基化合物的量子化学研究

Investigation of Quantum Chemistry on Carbonyl Compounds of Bi-metal Tetrahedral Cluster Co_xM_(4_x)

本文对十个CO_xM_(4-x)异金属四面体簇合物体系进行了量化计算(DV-X_a方法)。结果表明:CO_xM_(4-x)异金属簇与Co_4四面体簇化学键相似,但其他金属(M)的引入,使四面体簇价带收缩,Co的3d能级展宽,体系费米能级升高。在Co与Fe、Ru等ⅦB族元素形成的双金属簇中,Co在簇中所占比例愈大,贡献的电荷就愈多;而在Co与Mo、W等ⅥB族元素形成的四面体簇中,Mo、W为电荷主要提供者。

Quantum chemistry calculation of ten tetrahedral cluster compounds CoxM4-x(CO)12(M = Fe,Ru,O3,Pt,Mo,W;X=1,2,3) has been performed by using DV-X, method. The results show that chemical bonds of bi-metal cluster CoxM4-x are analogous to those of mono-metal cluster Co.,. But interjection of another metal into the cobalt cluster causes contraction of valence band of the tetrahedral cluster, expansion of 3d energy level of the cobalt and rise of Fermi energy of system. For bi-metal cluster formed from cobalt with iron or ruthenium etc, the greater the proportion of cobalt in the cluster, the more cobalt contributes charges. In the cluster formed from cobalt with VIB group elements, molybdenum or tungsten is major contributor of charges.