Thermal decomposition mechanism of dimethyl(acetylacetonato)gold(III): Quantum chemical modeling

Abstract

Different mechanisms of the thermal decomposition of the complex [(CH3)2Au(acac)] and the subsequent formation of Au particles are considered using density functional theory. The first decomposition step is the intramolecular reductive elimination of the methyl groups yielding ethane and the complex [Au(acac)], which dimerizes into the dinuclear complex [Au2(acac)2] with an energy gain. The presence of the coordinatively unsaturated center [Au(acac)] results in a considerable decrease in the activation energy of decomposition of the complex [(CH3)2Au(acac)]. The [Au2(acac)2] dimer undergoes association, again with an energy gain, to form linear polymer chains with short Au-Au bonds, which act as the nanoparticle nucleation centers.