Zn3BSi5+: a two-layer molecular rotor with a planar pentacoordinate boron

Abstract

The first silicon-based two-layer molecular rotor C_s Zn₃BSi₅⁺ with a planar pentacoordinate boron was predicted. It is a global minimum structure formed by a Zn₃ triangle facing a BSi₅ wheel. Interestingly, it is dynamically fluxional at 600 K: the Zn₃ triangle can rotate freely on the BSi₅ wheel along the central axis. The two-layer Zn₃BSi₅⁺ cluster has 2σ/10σ/6π three-fold aromaticity, facilitating its dynamic fluxionality.