Basicity of bisperhalophenyl aurates toward closed-shell metal ions: metallophilicity and additional interactions

Abstract

The interaction of bisperhalophenyl aurates [AuR2]− (R = C6F5, C6F3Cl2, and C6Cl5) with the closed-shell Ag+, Cu+, and Tl+ ions has been studied theoretically and compared with the experimentally known X-ray diffraction crystal structures. Initially, the aurates have been fully optimized at MP2 level of theory in a D2h symmetry. The analysis of the basicity of the three aurates [AuR2]− (R = C6F5, C6F3Cl2 and C6Cl5) against Ag+ ions in a C2v symmetry has been calculated in point-by-point bsse-corrected interaction energy analysis at HF and MP2 levels of theory. Taking into account the experimental observation of additional interactions between the heterometals and Cipso atoms at the perhalophenyl rings or halogen atoms at the ortho position of the perhalophenyl rings, dinuclear models of the type [AuR2]−···Ag+ (R = C6Cl5, and C6F5); [AuR2]−···Cu+ (R = C6F5, and C6Cl5) and [AuR2]−···Tl+ (R = C6F5, and C6Cl5) with a C2v, C2, and Cs symmetries have been optimized at DFT-B3LYP level. The interaction energies have been computed through bsse-corrected single point HF and MP2 calculations. The energy stabilization provided and the heterometal preference have been analyzed and compared with the experimental results.