Electronic states of Cu(1 1 1)/C₆H₆. A dielectric continuum approach and a heterogeneous solvation model

A recently presented dielectric continuum model is extended to a metal coated with two dielectric layers. The potential energies, binding energies and wave functions of the image potential states are presented as a function of the electron affinities and dielectric constants of the dielectric media. The double dielectric continuum model (DDCM) is compared with the single dielectric continuum model (SDCM). The heterogeneous reaction field solvation model enables the computation of the dielectric constant of a molecular layer adsorbed on the surface of a perfect conductor. The dielectric constant is presented as a function of the orientation of the molecule relative to the surface of the perfect conductor. The computed dielectric constants are used for computing the binding energies and wave functions of the lowest lying electron states of a Cu(1 1 1)-surface covered with a monolayer or bilayer of benzene. The estimated binding energies are compared with the ones measured experimentally by Velic et al. [J. Chem. Phys. 109 (1998) 9155].