Abstract
We present new interatomic potentials with which to model the structures and stabilities of the zinc-blende and wurtzite polytypes of and . The potentials are able to reproduce many of the properties of all four minerals to within a few percent of the experimental values. In contrast to the majority of previous forcefields, the calculated relative stabilities of the cubic and hexagonal phases are found to be in the correct order for both and , with the key being the inclusion of a four-body contribution to the energy. For , the cubic polytype is predicted to be the most favorable while for , the hexagonal phase is the more stable. In solid solutions of we find that the transition from hexagonal to cubic occurs for a composition of .
- Received 6 January 2004
DOI:https://doi.org/10.1103/PhysRevB.70.035211
©2004 American Physical Society