CI Study of CO adsorption on MgO(1 0 0)

Using CI embedding method, we have studied the adsorption of CO on MgO(1 0 0). The MgO(1 0 0) substrate is described by a Mg9O9 (3 × 3 × 2) core cluster, embedded in ionic (Mg2+/O2−) core potentials. The adsorption energy is calculated to be 0.11 eV at the CI level with a blue shift of 19 cm−1 for CO stretching on MgO(1 0 0). The dispersion accounts only 35% of the total binding energy of CO on MgO(1 0 0). The CO/MgO(1 0 0) interaction is weak and mainly of the van der Waals type with only slight chemical bonding characters.