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-order finite-difference-pseudopotential (FDP) method to calculate the interatomic forces. Our approach is compared to molecular-dynamics-simulation 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 space, and is easier to implement than methods based on a plane-wave expansion.