Adsorption of xenon on nickel films epitaxed on sodium chloride

Abstract

Nickel films condensed in ultra-high vacuum on to a vacuum-deposited film of sodium chloride expose predominantly {100} crystal planes at the surface. The adsorption of xenon on this surface is measured at several temperatures in the range 77–90°K. Heats and entropies of adsorption are plotted as a function of coverage and the results compared with data from a nickel film on Pyrex. The method of computing adsorption parameters according to a patch model of a heterogeneous surface, previously used for nickel on Pyrex is applied to the present results to estimate the extent of the {100} nickel surface.