A theoretical study of the decomposition of gold (I) complexes

Structures, energetics and excitation energies are calculated for the gold (I) complexes CH3Au, (CH3)2Au−, CH3AuOH2, CH3AuPH3 and PH3AuCl at the Hartree–Fock and MP2 levels of theory, and for CH3AuP(CH3)3, CH3AuP(OH)3 and Au3Cl3 at the HF level. The lowest-energy neutral triplet state of each 2-coordinate compound dissociates into either two or three radical species (always including the CH3 radical), with the exception of (CH3)2Au− which shows only slight Au–C bond elongation. In contrast, the doublet anion states dissociate neutral ligands, like PH3, but do not dissociate CH3. These results indicate that gold (I) chemical vapor deposition processes must involve excited states of the neutrals rather than their anions.