High temperature elastic constants and the evaluation of effective pair potentials

It is shown by exampl e that the predi cted temperature depe nde nce of the elastic co nstants is a useful meas ur e of th e ability of an effective pair potential to estimate th e high temp eratur e th ermal properti es of a me tal.Our exampl e is based on a mode l pair pot e ntial constructed for aluminum.Thi s potential predicts th e low temperature elastic co nstants and phonon di sper s ion relations with good accuracy (± a few pe rcent).Th e high tempe rature elasti c co nsta nts for thi s mo de l potential are determined usi ng th e Mont e Carlo method and are found to be a pproximate ly independe nt of temperatur e .Since th e elas ti c co nstants of aluminum are s tr ongl y decreas ing functions of temperature, thi s pote ntial is see n to be a poor o ne for de termining th e proper ti es of aluminum.We conclude that th e te mpera tur e dependence of th e elastic co ns tants is a use ful furth er tes t of pair pote nti als whi ch satisfy th e low te mperatur e tes ts c urrently employed .