%0 Journal Article %T Water Chemisorption and Reconstruction of the MgO Surface %A K. Refson %A R. A. Wogelius %A D. G. Fraser %A M. C. Payne %A M. H. Lee %A V. Milman %J Physics %D 1995 %I arXiv %R 10.1103/PhysRevB.52.10823 %X The observed reactivity of MgO with water is in apparent conflict with theoretical calculations which show that molecular dissociation does not occur on a perfect (001) surface. We have performed ab-initio total energy calculations which show that a chemisorption reaction involving a reconstruction to form a (111) hydroxyl surface is strongly preferred with Delta E = -90.2kJ/mol. We conclude that protonation stabilizes the otherwise unstable (111) surface and that this, not the bare (001), is the most stable surface of MgO under ambient conditions. %U http://arxiv.org/abs/mtrl-th/9508001v1