title: Theoretical studies on the structure and aromaticity of Ti2P6+.
abstract: Cationic cluster Ti2P6+ has been studied within density functional theory. The structure of this cluster is predicted to be a slightly distorted tetragonal prism. The dissociation energy of this cationic cluster is higher than that of the known sandwich compound, [(P5)2Ti]2-, because of the different bonding in these two compounds. In Ti2P6+, the hybridization of P atoms of the ring is sp3. The bonding between the metal atoms and the P ring is mainly sigma-pi. While in [(P5)2Ti]2-, the P atoms take sp2 hybridization, the bonding between the metal atom and the rings is the typical pi-pi interaction. The electronic delocalization is another stabilizing factor for Ti2P6+. The nuclear independent chemical shift indicates that Ti2P6+ is a three-dimensional aromatic molecule. The predicted infrared and NMR help to identify the Ti2P6+ conformations in experiment.
authors.affiliation: State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin University, Changchun 130023, China.
authors.forename: Wei-Qi
authors.initials: WQ
authors.lastname: Li
authors.forename: Wei Quan
authors.initials: WQ
authors.lastname: Tian
authors.forename: Ji-Kang
authors.initials: JK
authors.lastname: Feng
authors.forename: Zi-Zhong
authors.initials: ZZ
authors.lastname: Liu
authors.forename: Ai-Min
authors.initials: AM
authors.lastname: Ren
authors.forename: Gang
authors.initials: G
authors.lastname: Zhang