Ab initio study of the reaction of H2 with an AuPt3 cluster -: art. no. 164302

The study of the interaction of a pyramidal tetramer of AuPt3 with H-2 is carried out by means of Hartree-Fock self-consistent field (SCF) calculations using relativistic effective core potentials and multiconfigurational SCF plus multireference variational and perturbational on second-order Moller-Plesset configuration interaction calculations. The AuPt3-H-2 interaction was carried out in C-s symmetry. The three lowest electronic states X (2)A('), A (2)A('), and a (4)A(') of the bare cluster were considered in order to study this interaction. The AuPt3+H-2 reaction by a Pt vertex shows that AuPt3 cluster in the three lowest-lying electronic states can spontaneously capture and dissociate the H-2 molecule. While, by the AuPt2 face side, the AuPt3 cluster only in the A (2)A(') electronic state can capture and dissociate the H-2 molecule after surmounting a small energy barrier. For the Au vertex, this cluster in the three electronic states can also spontaneously capture and dissociate the H-2 molecule. On the other hand, by the Pt-3 face side, the AuPt3 cluster is able to capture and dissociate the H-2 molecule after surmounting energy barriers, where the AuPt3 (X (2)A(') and (4)A('))-H-2 adsorption are slightly activated. (c) 2005 American Institute of Physics.