Probability of gas adsorption on metal films. Part 2.—Nitrogen on tungsten

Abstract

The factors relevant to the design of a flow-system for determining the sticking probabilities of gases on film surfaces are discussed critically. The sticking probability of nitrogen on tungsten films is 0.64 at 298°K and 0.94 at 77° and 130°K. These values, which are higher than those observed with tungsten ribbons, are in quantitative agreement with calculations based on a model for film surfaces suggested by Takaishi. The variation of the number of molecules adsorbed as a function of film weight has been analyzed in terms of equations based on a model for film growth and data determined previously with nickel films.