Surface morphology of the (0001) face of arsenic was characterized by the formation and growth of equilateral triangular and truncated triangular etch pits during free evaporation. The evaporation rate was correlated with observed changes in etch pit geometry and with the variation in intensity of a reflected gas‐laser beam. Experiments were supplemented by a computer simulation of free evaporation on the (0001) surface to provide a means for delineating the effect of the primary variables which control the morphology as well as the kinetic phenomena. The important controllable variables included the distribution between triangular and truncated forms, the growth rate, birth time, and the general geometric features of each pit. The birth time distribution strongly influenced the relationship between pit geometry and laser intensity. Other independent variables, such as the variation in the growth rate and degree of truncation, affected these quantities to a lesser extent.