Capillary-wave model for evaporation of a liquid

Local-mode capillary-wave theory has been used to calculate the rate of escape of molecules from a liquid surface for 12 different liquids. The results for a temperature of 298 K are sufficiently close to the experimental values to indicate that the main features of the model are correct, but the calculated temperature dependence of vapour pressure is smaller than observed. The calculated vapour pressure is very strongly dependent on the value assumed for the hard-sphere diameter of the molecules, so some of the missing temperature effect might be associated with a decrease in the effective collision diameter with increasing temperature.