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arXiv · mtrl-th/9508001

Water Chemisorption and Reconstruction of the MgO Surface

K. Refson·R. A. Wogelius·D. G. Fraser·M. C. Payne·M. H. Lee·V. Milman
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Abstract

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.

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K. Refson, R. A. Wogelius, D. G. Fraser, M. C. Payne, M. H. Lee, V. Milman. 1995-08-01. Water Chemisorption and Reconstruction of the MgO Surface. https://doi.org/10.1103/physrevb.52.10823

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