Mechanism of Interaction of Dimethylgold(III) Chelates Vapour with Hot Surface

Abstract
By the electron impact mass-spectrometric method, the temperature dependence of the gas phase structure was investigated at the thermal decomposition of dimethylgold chelate vapour of the general formula (CH₃)₂AuL, where L = (RC(X)CHC(Y)R¹) ; R = CH₃, C(CH₃)₃ ; R¹ = CH₃, C(CH₃)₃, CF₃ ; X = O, NH ; Y = O, S) in vacuum and deuterium environment at temperatures up to 350 °C and the saturated vapour pressure by 10^-4 - 10^-2 Torr. The threshold temperature of the stability of complexes vapour was determined. From the temperature dependence of the rate constant of decomposition processes the effective activation energy was obtained. It was shown that the initial act of the complexes destraction is break of the chelate cycle. The following decomposition process complexes adcorbed at the surface lead to HL, L and CH₃ L, methane and ethane by competitive inside-and intermolecular processes. The presence of deuterium (or hydrogen) in the reaction zone couses to decrease onset temperatures for all investigated compounds.