DESORPTION ENERGIES AVERAGED OVER THE DESORPTION PROCESS BY MODEL-CALCULATIONS

Model calculations are used to investigate the relation between the co verage-dependent desorption energies for the atoms of A(2)B(6) compoun ds and the desorption energies averaged over the desorption process. T he desorption energy of B atoms is assumed to decrease linearly with i ncreasing surface coverage of B atoms. The desorption energy pf A atom s is assumed to be independent of the coverage. Variation of the surfa ce coverage and the time necessary to obtain the equilibrium coverage after deposition of one element are calculated. The desorption energie s averaged over the desorption process are determined. The calculation s show that there is almost no difference between the averaged desorpt ion energies of different elements. The desorption energy averaged ove r the desorption process is independent of the initial surface coverag e.