五原子平面四配位碳分子CGa_3Pb和CGa_3Pb^-的理论研究（英文）

Theoretical studies on the penta-atomic planar tetracoordinate carbon molecules CGa_3Pb and CGa_3Pb^-

对五原子分子CGa_3Pb及CGa_3Pb^-进行了理论研究,分别得到了6个平面结构的异构体,最稳定的结构1(1a,1A)含有平面四配位碳,NBO分析发现了中心碳与周围配体形成了σ供键及π反馈键,NICS分析发现结构1具有σ及π双重芳香性。结果发现18价电子对平面结构稳定性具有重要的作用。

The pentaatomic molecules CGa3Pb and CGa3Pb^- have been studied by density functional theory （DFT）. Six planar geometry isomeric structures were gained, and the most stable structures 1 contain planar tetracoordinate carbons. Natural bond orbital （NBO） analysis indicates donating and back-donating carbon-ligand interactions. Nucleus independent chemical shifts （NICS） values show that structures 1 possess σ and π aromaticity. This analysis suggests that the presence of 18 valence electrons is crucial for the planar geometries to be stable and preferred over tetrahedral structures.