  Surface reconstructions on the polar ZnO(0001) surface are investigated using
empirical potential models. Several possible reconstructions based around
triangular motifs are investigated. The quenching of the dipole moment in the
material dominates the energetics of the surface patterns so that no one
particular size of surface triangular island or pit is strongly favoured. We
employ Monte Carlo simulations to explore which patterns emerge from a high
temperature quench and during deposition of additional ZnO monolayers. The
simulations show that a range of triangular islands and pits evolve in
competition with one another. The surface patterns we discover are
qualitatively similar to those observed experimentally.
