近三十年来,无机化学有了复兴,特别是在过渡金属有机金属化学方面,人们已制得了许多复杂的配合物和原子簇化合物。这些化合物的分子包括两部分:过渡金属和配体部分,即ML_n.例如,M(CO)_5、M(CO)_4、MCP(CP~-即C_5H_5~-)、Os_(?)(CO)_(1?)……。近十年来,霍夫曼(Roald Hoffmann)等用群论和扩展的休克尔分子轨道法进行近似处理,建立了构成这些分子的金属配体ML_n“碎片”(fragment)的前线轨道,並指出:研究这类化合物 Nearly three decades, inorganic chemistry has been revived, especially in the transition metal organometallic chemistry, people have made many complex complexes and cluster compounds. The molecules of these compounds are composed of two parts: the transition metal and the ligand part, namely ML_n. For example, M (CO) _5, M (CO) _4, MCP (CP ~ - namely C_5H_5 ~ _(1?)……. In the last decade, Roald Hoffmann et al. Used the group theory and the extended Huckleau molecular orbit approach to approximate the frontier orbits of the ML_n “fragments” that make up the metal ligands for these molecules, pointing out that: Study these compounds