物理化学学报 >> 1991, Vol. 7 >> Issue (01): 64-71.doi: 10.3866/PKU.WHXB19910110

研究论文 上一篇    下一篇

五配位双核铁簇合物的电子结构研究

刘光华; 黎乐民; 徐光宪; 梁珍璇   

  1. 北京大学化学系;中国科学院计算中心
  • 收稿日期:1989-12-20 修回日期:1990-05-08 发布日期:1991-02-15
  • 通讯作者: 黎乐民

Study on the Electronic Structure of Five Coordinate Iron-Sulfur Clusters with Two Irons

Liu Guang-Hua; Li Le-Min; Xu Guang-Xian; Liang Zhen-Xuan   

  1. Department of Chemistry, Peking University, Beijing; The Computer Center, the Chinese Academy of Sciences
  • Received:1989-12-20 Revised:1990-05-08 Published:1991-02-15
  • Contact: Li Le-Min

摘要: 本文研究了五配位铁簇合物[Fe(XCHCHS)_2]_2~(n-)[X=O,(Ⅰ); X=S, (Ⅱ), n=2,3,4]及其单体的电子结构, 分析了成键情况。Mossbauer谱四极矩分裂和化学位移计算值与实验结果符合很好。(Ⅰ) 的氧化型基态中铁的多重度为6, 而基态氧化型的(Ⅱ)中铁的多重度为4, 与实验结果一致。计算结果表明: 氧化还原过程是在铁上进行的, 但增加或减少的电子通过电荷弛豫分布到配体原子上。簇合物是由单体通过前线区轨道的相互作用二聚而成。对(Ⅰ)和(Ⅱ)构型不同的原因提出了解释。

关键词: 五配位铁簇合物, 电子结构

Abstract: The electronic structure and chemical bonding of the five coordinate iron clusters [Fe(XCHCHS)_2]_2~n-[X=O, (Ⅰ); X=S, (Ⅱ); n=2, 3, 4] and their monomers have been studied. The calculated data of the quadrupole splitting and chemical isomer shift are in good agreement with those of experiments.The multiplet of the iron in the oxidized ground state of cluster(Ⅰ) is 6, while that of (Ⅱ) is 4, in accordance with the experimental results. The calculation result shows that the oxidation-reduction process in fact takes place on iron, but the electrons gained or lost transfer to the ligand atoms through charge relaxation. The formation of these clusters can be considered as dimerization of two fragments through interaction of their orbitals in the frontier region. An explanation about the configuration difference between (I) and (II) is proposed.

Key words: Five coordinate iron clusters, Electronic structure