Hostname: page-component-7bb8b95d7b-fmk2r Total loading time: 0 Render date: 2024-10-06T09:45:57.568Z Has data issue: false hasContentIssue false

Cooperative Premelting Effects on a (110) FCC Surface: A Molecular Dynamics Study

Published online by Cambridge University Press:  25 February 2011

V. Pontikis
Affiliation:
Centre d'Etudes Nucléaires de Saclay, Section de Recherches de MétaLLurgie Physique, 91191 Gif sur Yvette, Cedex, France
G. Ciccotti
Affiliation:
Dipartimento di FisicaUniversita degli Studi “La Sapienza”, PLe ALdo Moro 5, 00185 Roma (ItaLy)
Get access

Abstract

The thermodynamicaL and structural behavior of a (110) face of a (12–6) Lennard-Jones fcc solid has been investigated by MoLecuLar Dynamics computer simulation on the solid-gas coexistence Line up to a temperature T= 0.94 TM (TM: melting point). We have found evidence for cooperative defect production on free surfaces which Leads to a structural transitiDn above T≈0.7 TM. This transition is studied using as an order parameter the excess energy for surface Layers due to missing bonds parallel to the surface with respect to the bulk. Furthermore we report the vaLues of the mean square displacement for surface and bulk atoms as a function of temperature. Despite their high values at the surface, surface Layers are not molten but only highly disordered above the transition temperature.

Type
Articles
Copyright
Copyright © Materials Research Society 1986

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1] Boyer, L.L., Phase Transitions 5 (1985) 1 CrossRefGoogle Scholar
[2] Landau, L.D. and Lifshitz, E.M., Course of Statistical Mechanics, ed. MIR Moscow (1965)Google Scholar
[3] Pietronero, L. and Tosatti, E., Solid State Commun. 32 (1979) 255 C.S. Jayanthi, E. Tosatti, L. Pietronero, Phys. Rev. B 31 (1985) 3456CrossRefGoogle Scholar
[4] Broughton, J.O. and Woodcock, L.V., J. Phys. C 11 (1979) 2743 CrossRefGoogle Scholar
[5] CotteriLL, R.M., Jensen, E.J., Kristensen, W.D., in Anharmonic Lattices, StructuraL Transitions and MeLting, edited by Rista, T. (NATO Advanced Study Institutes Series, Noordhoff Leiden, 1974), p. 405 CrossRefGoogle Scholar
[6] Rhead, G.H., Surface Sci. 15 (1969) 353; 22 (1970) 223CrossRefGoogle Scholar
[7] Gjostein, N.A., in Surfaces-and Interfaces: I ChemicaL and Physical Characteristics, Eds Burke, J.J., Reed, N.L. and Weiss, N.V. (Syracuse University Press, 1975) p. 279 Google Scholar
[8] Rosato, V., Ciccotti, G., Pontikis, V., in press on Phys. Rev. BGoogle Scholar
[9] Pontikis, V. and Rosato, V., 7th European Conference on Surface Science ECOSS-7, 1–4 April 1985, Aix-en-Provence (France), Surface Sci. 162 (1985) 150Google Scholar
[10] Burton, W.K., Cabrera, N., Frank, F.C., Phil. Trans. Roy. Soc. London 243 A (1951) 299 Google Scholar
[11] Allen, R.E., de Wette, F.W., Phys. Rev. 179 (1969) 873 CrossRefGoogle Scholar
[12] Allen, R.E., de Wette, F.W., Rahman, A., Phys. Rev. 179 (1969) 887 CrossRefGoogle Scholar
[13] Allen, R.E., de Wette, F.W., Phys. Rev. 188 (1969) 1320 CrossRefGoogle Scholar
[14] Hansen, J.P., Klein, M., Phys. Rev. B 13(1976) 878 CrossRefGoogle Scholar
[15] Morabito, J.M., Steiger, R.F., Samorjai, G.A., Phys. Rev. 179 (1969) 638 CrossRefGoogle Scholar
[16] Moleko, L.K. and Glyde, H.R., Phys. Rev. B 30 (1985) 4215-CrossRefGoogle Scholar