Band structure and thermodynamic properties of He atoms near a MgO surface

The energy-band structure and thermodynamic properties of a single He atom adsorbed upon MgO are computed numerically. The bound-state energy eigenvalues, wave functions, and matrix elements were obtained by solving the single-particle Schrödinger equation using the recently developed semi-empirical potential of Karimi and Vidali as input. We find at the center of the Brillouin zone an effective mass enhancement m^* m =1.081 that agrees well with the predictions of a perturbation theory. The heat capacity and isosteric heat of adsorption are calculated and compared to the data of Sullivan et al. [Surface Sci. 162 (1985) 461].