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对一系列金属碳化物簇进行了DV－Xa分子轨道计算，探讨了C2配位环境对电子结构的影响.计算结果表明，在La6C15+2簇中，La的5d和C的2p带分开，键基本上是离子性.当La原子被Ni取代形成La4Ni4C16+2簇之后，Ni的3d和C的2p带几乎完全重叠，表明了强的Ni－C共价作用．此外．在Sc5Ni4C18+2簇中，除Ni－C和C－C共价作用外，还存在着强的金属-金属键．
A series of metal carbide clusters were calculated by DV-Xa molecular orbital to investigate the effect of C2 coordination environment on the electronic structure. The calculated results show that in La6C15 + 2 clusters, 5d of La and 2p of C are separated, Is essentially ionic.When La atoms are replaced by Ni to form La4Ni4C16 + 2 clusters, the 3d of Ni and the 2p band of C almost completely overlap, indicating a strong Ni-C covalent effect. In addition. In Sc5Ni4C18 + 2 clusters, in addition to the covalent interaction between Ni-C and C-C, there are strong metal-metal bonds.