The development of a simple atomistic simulation of microstructural evoluti
on is illustrated for a two-dimensional system comprising of a monolayer of
inert gas atoms on a calcium (111) surface. The simulation results in the
formation and growth of domains, the domain size increasing as a function o
f simulation temperature and Bur of atoms incident on the surface. Of parti
cular interest is the observed nonlinear critical behaviour in the surface
coverage.