O activation by AuAg clusters on a defective (100)MgO surface.

In the present work, we discuss the electronic properties of supported dispersed bimetallic clusters with respect to their size, geometry, and Au/Ag (n + m = 6) composition. We have studied with supercell-density functional theory calculations the role of the charge transfer from the MgO defective support toward the cluster in the activation of O by AuAg clusters. We first considered gas-phase clusters with different atomic compositions; then, we deposited all of them on a pristine (100)MgO surface and finally on a more realistic (100)MgO F-center.