  We report an experimental and theoretical analysis of the root(3)xroot(3)-R30
and 2x2 reconstructions on the MgO (111) surface combining transmission
electron microscopy, x-ray photoelectron spectroscopy, and reasonably accurate
density functional calculations using the meta-GGA functional TPSS. The
experimental data clearly shows that the surfaces contain significant coverages
of hydroxyl terminations, even after UHV annealing, and as such cannot be the
structures which have been previously reported. For the 2x2 surfaces a
relatively simple structural framework is detailed which fits all the
experimental and theoretical data. For the root(3)xroot(3) there turn out to be
two plausible structures and neither the experimental nor theoretical results
can differentiate between the two within error. However, by examining the
conditions under which the surface is formed we describe a kinetic route for
the transformation between the different reconstructions that involves mobile
hydroxyl groups and protons, and relatively immobile cations, which strongly
suggests only one of the two root(3)xroot(3) structures.
