Planar tetracoordinate carbon species CLi3E with 12-valence-electrons

Abstract

We exhibit theoretically a series of 12-valence-electron pentaatomic species CLi₃E (E = N, P, As, Sb, Bi) and CLi₃E⁺ (E = O, S, Se, Te, Po). The analyses of potential energy surfaces indicate that the C_2v structures with a planar tetracoordinate carbon are the global minimum in these species except for E = N, P. A localized CE double bond is found in the planar tetracoordinate carbon species. The molecular orbitals and the valence populations reveal that the CE double bonds in CLi₃E are different from those in CLi₃E⁺. The thermodynamic and kinetic calculations show that some of the planar tetracoordinate carbon species are stable and are likely to exist in the gas phase.