BOND-ORDER POTENTIALS - THEORY AND IMPLEMENTATION

The background theory and the details required for implementation of b ond-older potentials are presented in a systematic fashion. The theory is an O(N) implementation of tight binding that is naturally parallel izable. Further, it is straightforward to show how the lowest-order ap proximation to the two-site expansion can reproduce the Tersoff potent ial. The accuracy of the forces is demonstrated by means of constant-e nergy molecular dynamics, for which the energy is found to be very wel l conserved. Thus, the method is both an efficient computational metho d and a useful analytic tool for the atomistic simulation of materials .