三羰基茂卤钼复合物的结构及Cp…Mo作用的研究

Study on the Structure and the Chemical Bond of the Tricarbonylcyclopentadienyl Halogen Molybdenum Complexes with Cp…Mo

利用Gaussian 03W程序,在LANL2DZ基组,对三羰基茂卤钼复合物进行理论研究,进行了全结构优化复合物体系的构型,振动频率分析结果表明复合物体系的结构稳定,在此基础上进行单点计算,结果表明,钼原子位于环戊二烯环上形成半夹心结构。复合物的键角、键长、Wiberg键级、原子电荷和体系能及前沿分子轨道组成分析表明,钼原子与环戊二烯之间通过p-π和d-π作用形成"氢键",环戊二烯碳上的p电子向钼原子的d轨道转移,形成电荷转移复合物。

A theoretical investigation of the title complexes as a structural unit was carried out using Gaussian 03W at LANL2DZ level. The possible geometries of the tricarbonylcyclopentadienyl halogen molybdenum complexes has been optimized. The cal- culated vibrational frequency show that the structures are reasonable. The most stable geometries of complexes are the configu ration where the molybdenum is located above the cyclopentadienyl ring by optimization and the single point energy calculation. The bond lengths, wiberg bond order,bond angle, atomic charge, the energies and the composition of the frontier molecular or- bitals of the complexes indicate that the interaction between molybdenum and cyclopentadienyl involve p-π and d-π interaction. Electron is transferred from the p orbital of carbon （cyclopentadienyl） to d orbital of molybdenum,and thus gives charge transfer complexes. The molybdenum- cyclopentadienyl complexes are similar to hydrogen bonding.