Theoretical Study on Geometries and Electronic Structures of Gold Halides and Polyhalides

Abstract

It is well known that gold can be dissolved in aqua regia. Recently, reversible dissolution/deposition of gold has been reported in organic solvent with excessive iodine. Effective dissolution occurs when comparable amounts of I3- and I- are present. To examine the geometries and electronic structures of gold halides, which is closely related to the dissolution/deposition reactions, ab initio MP2 and DFT B3LYP calculations were carried out using nonrelativistic, quasi-relativistic, and relativistic effective core potentials (ECPs). Geometries of diatomic molecules are compared experimental values. Relativistic effects shorten the bond lengths, which is in agreement with the previous works, by approximately 0.2 A. There is not much difference in the calculated bond lengths between MP2 and B3LYP. Optimized geometric parameters of linear triatomic anions of gold halides are also compared with the experimental ones. Studies on geometries and electronic structures of pentaatomic anions of gold halides and polyhalides are in progress.