title: Octacoordinate metal carbonyls of lanthanum and cerium: experimental observation and theoretical calculation.
abstract: The octacoordinate metal carbonyls La(CO)8(+) and Ce(CO)8(+) were observed in laser vaporization of La and Ce in pure CO gas. The peak intensities in the mass spectra, the infrared photodissociation spectra, and the theoretical calculations indicate that all CO ligands in these two complexes are bonded with the central metal atoms. The CO stretching frequencies in La(CO)8(+) and Ce(CO)8(+) are determined to be 2110 and 2108 cm(-1), respectively. Theoretical studies indicate that the most stable structures for La(CO)8(+) and Ce(CO)8(+) are an Oh geometry at its triplet state and a slightly distorted Oh geometry at its quartet state, respectively. These two complexes represent new octacoordinate metal carbonyls after previously determined U(CO)8(+) and Y(CO)8(+).
authors.affiliation: State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Dalian 116023, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Xie
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.forename: Zhengbo
authors.initials: Z
authors.lastname: Qin
authors.forename: Lei
authors.initials: L
authors.lastname: Shi
authors.forename: Zichao
authors.initials: Z
authors.lastname: Tang
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Xing