Clausius-Clapeyron equation analysis of two- dimensional vaporization

Abstract The temperature dependence of the work function change caused by adsorption of Cu, Ag, Au, Ni and Pd on W(110) and of Ag and Au on W(211) is analyzed with the aid of the Clausius-Clapeyron equation. It is found that the heat of two-dimensional evaporation has a high and a low temperature value which indicates evaporation from smooth island edges at low temperature and rough edges at high temperature. A two-dimensional roughening transition is implied.