Abstract
The equivalent core approximation (Z+1) is used with a Born–Haber cycle analysis to analyze the Ni 2p3/2 surface core-level binding-energy shifts which occur upon adsorption of CO, H, and O on Ni(100). The analysis gives values for the heats of desorption of these gases from Cu–Ni alloy surfaces. Perhaps more importantly, it also provides a quantitative determination of how chemisorption of CO, H, and O modify the heats of surface segregation for Cu–Ni surfaces.