Quantum chemical calculations of the structures, stabilities, and metalophilic interactions of AuX halides (X = FAt) at the CCSD(T) theoretical level with extended basis sets were performed. Natural bond orbital analysis showed that the present gold–halide metalophilic interactions mainly resulted from the overlap of an sp hybrid on halogen and a 6s6p5d hybrid on the Au atom. Analysis of electron density deformation showed a pronounced charge accumulation in the middle of the region between heavier X and Au, and clearly suggested the formation of covalent bond. Topological analysis of the Laplacian and total electronic energy densities at bond critical points showed the “intermediate type” character of gold–halide metalophilic interactions. Electron localization function showed the increased covalency from X = F to X = At. © 2014 Wiley Periodicals, Inc.