Summary: PHYSICAL REVIEW B 84, 235442 (2011)
Molecular dynamics study of melting of the hcp metal Mg
P. Bavli, E. Polturak, and Joan Adler*
Physics Department, Technion-Israel Institute of Technology, Haifa 32000, Israel
(Received 12 September 2011; revised manuscript received 11 December 2011; published 27 December 2011)
We present molecular dynamics simulations of the melting transition of Mg, an hcp metal, using the potential
developed by Sun et al. This study was motivated by the question of whether the hierarchy of premelting
phenomena, found to occur between different facets of metals with an fcc or bcc structure, is also present in
hcp metals. We first determined the structural and energetic properties of the effectively infinite solid with no
boundaries. We then investigated the low-index surfaces of Mg, namely the c (0001), a (1010), and s (1011) facets.
We found that as the temperature increases, the (1010) surface disorders first, followed by the (1011) surface,
while the (0001) surface remains stable up to the melting temperature. The disorder spreads from the surface
into the bulk, establishing a thin quasiliquid film in the surface region. We conclude that the effect of premelting
phenomena is inversely proportional to the surface atomic density, being most pronounced at the a (1010) facet
which has the lowest density. This conclusion is in line with the behavior found for fcc and bcc metals.
DOI: 10.1103/PhysRevB.84.235442 PACS number(s): 68.35.Rh, 64.70.dj, 83.10.Rs
Theories of melting13
can be separated into two classes.
The first one describes the mechanical melting of a homo-