Electron correlation contribution to the physisorption of CO on MgF 2(110)

Abstract

We have performed CCSD(T), MP2, and DF-LMP2 calculations of the interaction energy of CO on the Mg F 2(110) surface by applying the method of increments and an embedded cluster model. In addition, we performed periodic HF, B3LYP, and DF-LMP2 calculations and compare them to the cluster results. The incremental CCSD(T) calculations predict an interaction energy of E int -0.37 eV with a C-down orientation of CO above a Mg 2+ ion at the surface with a basis set of VTZ quality. We find that electron correlation constitutes about 50 of the binding energy and a detailed evaluation of the increments shows that the largest contribution to the correlation energy originates from the CO interaction with the closest F ions on the second layer. © 2012 American Institute of Physics.