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Thermal Contraction and Disordering of the Al(110) Surface

Nicola Marzari·David Vanderbilt·Alessandro De Vita·M. C. Payne
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Abstract

Al(110) has been studied for temperatures up to 900 K via ensemble density-functional molecular dynamics. The strong anharmonicity displayed by this surface results in a negative coefficient of thermal expansion, where the first interlayer distance decreases with increasing temperature. Very shallow channels of oscillation for the second-layer atoms in the direction perpendicular to the surface support this anomalous contraction, and provide a novel mechanism for the formation of adatom-vacancy pairs, preliminary to the disordering and premelting transition. Such characteristic behavior originates in the free-electron-gas bonding at a loosely packed surface.

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Nicola Marzari, David Vanderbilt, Alessandro De Vita, M. C. Payne. 1999-03-09. Thermal Contraction and Disordering of the Al(110) Surface. https://doi.org/10.1103/physrevlett.82.3296

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