Atomic layering at the liquid silicon surface: A first-principles simulation

G. FABRICIUS; E. ARTACHO; D. SÁNCHEZ-PORTAL; P. ORDEJÓN; D.A. DRABOLD; J.M. SOLER

PHYSICAL REVIEW B

AMER PHYSICAL SOC

Lugar: New York; Año: 1999 vol. 60 p. 16283 - 16287

1098-0121

We simulate the liquid silicon surface with first-principles molecular dynamics in a slab geometry. We find that the atom-density profile presents a pronounced layering, similar to those observed in low-temperature liquid metals like Ga and Hg. The depth-dependent pair correlation function shows that the effect originates from directional bonding of Si atoms at the surface, and propagates into the bulk. The layering has no major effects in the electronic and dynamical properties of the system, that are very similar to those of bulk liquid Si. To our knowledge, this is the first study of a liquid surface by first-principles molecular dynamics.