Abstract:

The characteristics of CO and NO adsorptions on surfaces of CuO(110) andCu2O(110) have been studied by using Self- Consistent-Charge Discrete Variational XαMethod (SCC-DV-Xα for short). The calculated results show that the molecules CO and NO are perpendicularly adsorbed on cuprous of Cu2O and cupric of CuO bonded with C and N atoms respectively. The order of chemisorption potential of the four adsorbed systems are: CuO-NO>Cu2O-CO>Cu2O-NO>CuO-CO. For CO or NO molecule chemisorbed on cupric oxide, the chemisorbed bonds are mainly contributed by the interactions of 3d orbitals of cupric with 2π molecular orbital (MO) of the adsorbates. While for CO or NO molecule chemisorbed on cuprous oxide, the chemisorbed bonds are mainly formed by the interaction of 3d orbitals of the top site Cu+ and 4s, 4p orbitals of the side site Cu+ with 5σ and 2π MO of adsorbates. Theses conclusions coincide with the experimental observations[1-7]. The selective chemisorptions of CO and　NO on the (110) surface of cupric and cuprous oxides are discussed by analysis of the potential curve, density of states （DOS）, bonding characters and the electrons transfers.

Key words: DV-X_a, CO and NO chemisorbed selectivity, CuO and Cu₂O(110) surfaces