Density matrix theory and calculations of nonlinear yields of CO photodesorbed from Cu(001) by light pulses

Bonding and excitation in CO∕Cu(001) from a cluster model and density functional treatments

The bonding properties and charge distributions of the COCu(001) system have been studied within density functional theory (DFT) with several density functionals. A Cu18(9,4,5)CO three layer cluster was found to give bond distances and energies in agreement with previous experimental and theoretical results for low coverage systems, provided the atomic basis set includes diffuse orbitals and d-orbitals at the Cu atoms. Charge distributions give insight on the nature of the localized adsorbate bonding. Time-dependent DFT results on excitation energies and on transition and average electric dipoles, relevant to photodesorption, are also presented.