Quasiequilibrium Treatment of Gas–Solid Reactions. II. Flash Desorption of Oxidation Products from a Tungsten Surface

Abstract

The quasiequilibrium treatment of heterogeneous reactions is applied to the flash desorption data of Ptushinskii and Chuikov [Surface Sci. 6, 42 (1967)] for the reaction of oxygen with a tungsten surface. Comparison of the theoretical and experimental results provides support for the view that, in the present case, flash desorption may be considered to be a quasistatic process (i.e., the adsorbate passes through a continuous series of equilibrium states). On this basis, the quasiequilibrium treatment is used to develop a semiquantitative explanation of the experimental observation that the amounts of the various oxide species desorbed per flash depend upon the adsorption temperature.