Chemisorption at finite coverages—the coherent potential approximation vs the equation of motion for green's functions method

Abstract

The electronic structure, chemisorption energy and adatom charge of the chemisorbed overlayer on a metal surface are studied within the model by the Newns Hamiltonian generalized to finite coverages. It is shown that the method of equation of motion for appropriate Green's function together with some decouplings of the higher-order Green's functions can be used in calculations of the overlayer's electronic properties as an efficient and alternative way to the coherent potential approximation method.