Planar hexacoordinate heavier tetrels

Abstract

Planar hexacoordination is a rare phenomenon in structural chemistry. Herein, we report planar hexacoordinate tetrel atoms (Si-Pb) in the D3h global minima of XBe3Li3H6− (X = Si, Ge) and YMg3Na3H6− (Y = Sn, Pb) clusters. The proposed clusters are thermodynamically stable and resistant to disintegration. Molecular dynamics simulation also reveals their dynamic stability up to a time period of 15 ps at 75 K. Bonding analyses reveal significant orbital overlap between the central tetrel atom and the surrounding ligand framework supporting true hexacoordination. Significant diatropic ring currents are present around the central tetrel atoms.