Temp.-dependent rf-ion trap mass spectrometry and first-principles simulations reveal the detailed reaction mechanism of the catalytic gas-phase oxidn. of CO by free Au2- ions in the presence of O2. A metastable intermediate with a mass of Au2CO3- was obsd. at low temps. Two alternative structures corresponding to digold carbonate or peroxyformate are predicted for this intermediate. Both structures are characterized by low activation barriers for the formation of CO2. These combined exptl. and theor. investigations provide a comprehensive understanding of the kinetics, energetics, and at. arrangements along the reaction path, thus allowing a formulation of the catalytic cycle for the oxidn. reaction. [on SciFinder(R)]     «

Temp.-dependent rf-ion trap mass spectrometry and first-principles simulations reveal the detailed reaction mechanism of the catalytic gas-phase oxidn. of CO by free Au2- ions in the presence of O2. A metastable intermediate with a mass of Au2CO3- was obsd. at low temps. Two alternative structures corresponding to digold carbonate or peroxyformate are predicted for this intermediate. Both structures are characterized by low activation barriers for the formation of CO2. These combined exptl. and...     »