COVERAGE DEPENDENT CHANGES IN THE BARIUM OVERLAYER ELECTRONIC-STRUCTURE ON NI(111)

We have investigated barium overlayers on Ni(111). We have been able to observe the barium 5s to 6p photoemission resonance. From resonant photoemission we can identify changes in the barium electronic structure at the Fermi energy with coverage. There is a 0.8±0.2 eV binding energy increase in the barium 5p shallow core levels with increasing overlayer thickness akin to a surface to bulk core level binding energy shift. © 1990.