AB-INITIO MOLECULAR-DYNAMICS SIMULATIONS OF SI CLUSTERS USING THE HIGHER-ORDER FINITE-DIFFERENCE-PSEUDOPOTENTIAL METHOD

We perform ab initio molecular-dynamics simulations using the higher-o rder finite-difference-pseudopotential (FDP) method to calculate the i nteratomic forces. Our approach is compared to molecular-dynamics-simu lation calculations where the forces are calculated using a plane-wave basis. The ground-state structures of small silicon clusters obtained from the FDP simulation are in excellent agreement with those of the plane-wave method. The FDP method is performed completely in real spac e, and is easier to implement than methods based on a plane-wave expan sion.