Investigation into relative stability of structural and electron characteristics of gold complexes [AuX2]- (X = SCN, CN, F, Cl, Br, I) and [Au(SC(NH2)2)2]+ by methods of quantum chemistry

Quantum chemical calculations of the electron structure of complex ions of gold Au+ are performed taking into account the solvent effects. The account of the solvent influence provided the quality agreement of the calculated series of deformation energies of the coordination bond (Delta E (0)) with the experimental series of stability constants of gold complexes (SCN similar to Cl < Br < I a parts per thousand(a) CN). Populations of outer orbitals and the effective atomic charge of gold in the [Au(X)(2)](-) complexes are calculated. The effective atomic charges of gold in the series under consideration vary from 0.096e for the fluoride complex to 0.396e for the thiocarbamide complex, with a formal oxidation level of gold of +1. The results of calculations make it possible to eliminate the apparent contradictions between the experimental data acquired by various methods and to interpret them in the framework of notions of gold sorption in the composition of the [Au(CN)(2)](-) complex.