Ab Initio Theoretical Investigation on the Geometrical and Electronic Structures of Gallium Aurides: Ga Aun0/- and Ga2Aun0/- (n = 1–4)

Abstract

This study presents a systematic investigation of the geometric and electronic properties of GaA and Ga2A (n = 1–4) clusters based on density functional theory and wave function theory. Detailed orbital analyses, adaptive natural density partitioning, and electron localization function analyses are performed and relevant results are discussed. GaA (n = 1–4) clusters with n‐Au terminals and Ga2A (n = 1–4) clusters with bridged Au atoms possess geometric structures and bonding patterns similar to those of the corresponding gallium hydrides Ga and Ga2. Ga–Au interaction is predicted to occur through highly polar covalent bonds in monogallium aurides. In contrast to the highly symmetric ground states of C2v Ga2Au, C2v Ga2Au2, and D3h Ga2Au3, C3v Ga2Au4 is composed of strong interactions between a Ga+ cation and the face of a tetrahedral GaA anion. The adiabatic and vertical detachment energies of the anions under study are calculated to facilitate their experimental characterization. Geometric and electronic structural comparisons with the corresponding gallium hydrides are conducted to establish an isolobal analogy between gold and hydrogen atoms.