In this paper, the molecular structure and chemical bonding of lanthanum monocarbokide have been studied with the density functional theory method. It is found that lanthanum monocarbokide can exist in two structures, LaCO and LaOC, that is,there exists linkage isomerism in lanthanum monocarboxide.
The geometry,electronic stucture and bond of L a CO,one of the rare earth carbonyl compounds,havebeen studied with SCM- DV- Xαmethod.From the resultsitiscertified thatthe L a CO isalinearmolecule,in which thebond length of L a- C and C- O are 0 .2 2 73nm and 0 .1179 nm respectively,theσcoordinatebond and theπ- back bond are formed between L aand CO. Itis also showed thatthe L a- C bond hasaboutmorethan90 % covalentcharacter and the4 f orbitals play a certain role in the bonding of La CO.
