Thermal contraction and disordering of the Al(110) surface

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 behaviour originates in the free-electron-gas bonding at a loosely packed surface. [S0031-9007(99)08925-5].


Published in:
Physical Review Letters, 82, 16, 3296-3299
Year:
1999
ISSN:
0031-9007
Keywords:
Laboratories:




 Record created 2012-06-29, last modified 2018-03-17


Rate this document:

Rate this document:
1
2
3
 
(Not yet reviewed)