Influence of k-point sampling on stability of structures obtained by ab initio MD simulations Original Research Article

By introducing the fractional occupation of the energy levels and increasing the number of k-point sampling, we studied how the lattice parameters of crystalline Si were improved in constant pressure ab initio molecular dynamics simulations. The deformation in β-tin structure was considerably reduced as the number of k-point was increased. A phase transition from diamond to the simple hexagonal structures is reproduced in simulation with 64 k-points.