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The electronic structures of red roussinate and black roussinate
Author(s) -
ChunWan Liu,
HuaiZhen Cao,
JiaXi Lu,
ShiJuin Zheng,
RuoZhuang Liu
Publication year - 1987
Publication title -
acta chimica sinica english edition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.28
H-Index - 41
eISSN - 1614-7065
pISSN - 0256-7660
DOI - 10.1002/cjoc.19870050102
Subject(s) - chemistry , cndo/2 , delocalized electron , cluster (spacecraft) , crystallography , atomic orbital , molecular orbital , metal , bond strength , three center two electron bond , atomic physics , computational chemistry , bond order , chemical physics , electron , bond length , molecule , crystal structure , physics , organic chemistry , quantum mechanics , computer science , programming language , adhesive , layer (electronics)
The electronic structures of the black roussinate monoanion, the first step model compound of the Fuzhou model‐I (the “String bag cluster model”) of the active center of nitrogenase, and its “cluster fragments”, the red roussinate dianion, have been calculated by using the close shell CNDO/2 (S,D scheme) method. From the analysis of the bonding properties on the basis of Mülliken populations, charge densities, MO energies and MO characters, the following results have been revealed. The intensive electron delocalization has been found in these two clusters. In the process of electronic transfer from the red roussinate to the black roussinate, the sulfur is an electron donor. There exists a certain degree of M‐M bonding in these two clusters. The strength of M‐M bond is near to that of M‐S b bond; the main contribution to these bonds is the interaction between the s, p, and d z 2 orbitals on the metal atoms, and the s and p z orbitals on the sulfur atoms. The contribution of the π interaction between the d orbitals on the metal atoms to the bonding of the cluster skeleton is quite small.