Computer simulation of local order in condensed phases of silicon
Abstract
A model potential-energy function comprising both two- and three-atom contributions is proposed to describe interactions in solid and liquid forms of Si. Implications of this potential are then explored by molecular-dynamics computer simulation, using 216 atoms with periodic boundary conditions. Starting with the diamond-structure crystal at low temperature, heating causes spontaneous nucleation and melting. The resulting liquid structurally resembles the real Si melt. By carrying out steepest-descent mappings of system configurations onto potential-energy minima, two main conclusions emerge: (1) a temperature-independent inherent structure underlies the liquid phase, just as for ``simple'' liquids with only pair interactions; (2) the Lindemann melting criterion for the crystal apparently can be supplemented by a freezing criterion for the liquid, where both involve critical values of appropriately defined mean displacements from potential minima.
- Publication:
-
Physical Review B
- Pub Date:
- April 1985
- DOI:
- 10.1103/PhysRevB.31.5262
- Bibcode:
- 1985PhRvB..31.5262S
- Keywords:
-
- 61.20.Ja;
- 61.20.Qg;
- 64.70.Dv;
- 05.70.Fh;
- Computer simulation of liquid structure;
- Structure of associated liquids: electrolytes molten salts etc.;
- Solid-liquid transitions;
- Phase transitions: general studies