MAEAM simulation of phonons for BCC transition metals

Combining MAEAM with the lattice dynamics, the atomic force constants and phonon dispersion curves have been obtained along five symmetry directions [0 0 ζ], [0 ζ ζ], [ζ ζ ζ], [1212ζ] and [ζ ζ 1] for three BCC transition metals Ta, W and Mo within interactions out to the sixth neighbors. The calculated results that are nearly in agreement with available experimental results along [0 0 ζ], [0 ζ ζ] and [ζ ζ ζ] directions implies that the predicted phonon dispersion curves along [1212ζ] and [ζ ζ 1] directions are well behaved. Along each symmetry direction, the vibration frequency that increases for Ta, W and Mo successively may be related to the ratio of cohesive energy Ec to mass M.