POTENTIALS FOR THE APPROACH OF A HYDROGEN-ATOM TO AN ALUMINUM METAL

The potential curves when a hydrogen atom is absorbed into aluminum through the lattice gate on the surface are obtained by an ab initio molecular orbital method with cluster models which consist of a hydrogen atom and several aluminum atoms. The calculations are carried out on the (100) and the (111) surface gates. It is found that the electron correlation lowers the potential barrier from the outside to the inside and shifts the inside minimum points to the higher symmetrical site, T(d) or O(h). Moreover, the results suggest the possibility that a more stable site than the adsorption site on the surface exists at the octahedral site between the surface and the second layer.