Mechanism of the Oxidation Reaction of Cu with N 2 O via Nonadiabatic Electron Transfer EUGENE S. KRYACHKO, 1,2 OKSANA TISHCHENKO, 1 MINH THO NGUYEN 1 1 Department of Chemistry, University of Leuven, Celestijnenlaan 200 F, B-3001 Leuven, Belgium 2 Bogoliubov Institute for Theoretical Physics, Kiev 03143, Ukraine Received 1 October 2001; accepted 1 October 2001 Published online 9 July 2002 in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/qua.10296 ABSTRACT: We treat the present work as an attempt to elucidate the mechanism of the oxidation reaction of the Cu atom by nitrous oxide based on our recent work (Kryachko, E. S.; Vinckier, C.; Nguyen, M. T. J Chem Phys 2001, 114, 7911) on the electron attachment to this molecule. We suggest that the title reaction in its Arrhenius regime occurs via the nonadiabatic electron transfer from Cu to the oxygen atom at the crossing of the potential energy surfaces Cu(4s 2 S 1/2 ) + N 2 O(X 1  + ) and Cu + + N 2 O - , where the latter is linked to the complex N 2 O - originated from the higher-energy T-shape N 2 O molecule and discovered in the aforementioned work. The calculations performed in the present work using a variety of quantum chemical methods support the proposed model. We also show the existence of other reaction pathways of the title reaction that, we believe, contribute to its non-Arrhenius behavior observed experimentally at T  1190 K. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem 89: 329 –340, 2002 Key words: nitrous oxide; oxidation reaction of Cu with N 2 O; crossing of potential energy surfaces; Arrhenius regime 1. Introduction N itrous oxide (N 2 O) is an important long-lived gas whose increasing concentration in the at- mosphere and known ability to deplete the ozone layer and contribute to the greenhouse effect has recently become a subject of intensive study and debate [1] mainly focusing on the mechanisms reg- ulating N 2 O production and balancing it with the consumption of N 2 O. The latter task opens a wide area of modeling and understanding the favorable mechanisms of the reduction of the N 2 O emission. One of them leading actually to the decomposition of N 2 O is to use heterogeneous catalysts including transition metals, copper in particular [2, 3]. As is well known, the oxidation reaction of N 2 O with metal atom resulting in the metal oxide and N 2 as Correspondence to: E. S. Kryacko; e-mail: Eugene.Kryachko@ chem.kuleuven.ac.be This article is dedicated to the memory of Professor Ivan Zhelyaskov Petkov who, together with Professor Mario Stoitsov and one the authors (E. S. K.) proposed nearly 20 years ago the local-scaling density functional theory for many-electron sys- tems. International Journal of Quantum Chemistry, Vol 89, 329 –340 (2002) © 2002 Wiley Periodicals, Inc.