Theoretical ab initio study of NO and CO depollution reaction catalyzed by zinc

The reaction between NO and CO leading to N-2 and CO2 is the most studied depollution process of the former molecules. Ab initio study of a multi-stage mechanism of this reaction catalyzed by zinc was performed at SCF level. Many intermediates, such as ZnCO, ZnNO, ZnO and NCO, intervene in the proposed mechanism. Geometrical parameters, atomic charge, dipole moment and vibrational normal mode wave numbers of intervening molecules were calculated. Thermochemistry parameters (DeltaH, DeltaG, DeltaS) were also obtained. Transition state has been determined and has also allowed us to discuss the reaction mechanism. (C) 2001 Elsevier Science B.V. All rights reserved.