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Crossover between ionic/covalent and pure ionic bonding in magnesium oxyde clusters

F. Calvo
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Abstract

An empirical potential with fluctuating charges is proposed for modelling (MgO)_n clusters in both the molecular (small n) and bulk (n->infty) regimes. Vectorial polarization forces are explicitely taken into account in the self-consistent determination of the charges. Our model predicts cuboid cluster structures, in agreement with previous experimental and theoretical results. The effective charge transferred between magnesium and oxygen smoothly increases from 1 to 2, with an estimated crossover size above 300 MgO molecules.

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F. Calvo. 2003-01-23. Crossover between ionic/covalent and pure ionic bonding in magnesium oxyde clusters. https://doi.org/10.1103/physrevb.67.161403

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