Density functional study of aurophilic interaction in [X(AuPH3)2+]2 (X = F, Cl, Br, I)

Abstract

Several closed-shell systems [X(AuPH₃)₂⁺]₂ (X = F, Cl, Br, I) have been theoretically investigated by using density functional theory (DFT) and second order Møller–Plesset (MP2) methods in order to study the intermolecular aurophilic interaction. We studied the geometry of the structures, natural bond orbital (NBO) populations and the HOMO–LUMO gap of the title compounds. Experimental structural parameters of the title compounds were reproduced at the Xα level. The predicted experimental Au–F–Au and P–Au–F angles are 119.1 ± 0.5° and 178.4 ± 0.5°, respectively. The intermolecular aurophilic interaction energy is decomposed and analyzed. The chemical deformation electronic density is obtained to analyze the intermolecular interaction.