Ab InitioTheoretical Investigation on the Geometrical and Electronic Structures of Gallium Aurides:GaAun0/-andGa2Aun0/- (n=1–4)

Abstract

This study presents a systematic investigation of the geometric and electronic properties of GaAun0/-and Ga2Aun0/-(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. GaAun0/-(n= 1–4) clusters withn-Au terminals and Ga2Aun0/-(n= 1–4) clusters with bridged Au atoms possess geometric structures and bonding patterns similar to those of the corresponding gallium hydrides GaHn0/-and Ga2Hn0/-. Ga–Au interaction is predicted to occur through highly polar covalent bonds in monogallium aurides. In contrast to the highly symmetric ground states ofC2vGa2Au,C2vGa2Au2, andD3hGa2Au3,C3vGa2Au4is composed of strong interactions between a Ga+cation and the face of a tetrahedral GaAu4−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.