On the internal equilibrium in h.c.p. metals

Abstract

Recently a number of phenomenological models have been developed to explain the lattice dynamics of h.c.p. metals None of these models takes complete account of equilibrium in this metallic system. Two equilibrium conditions necessary for h.c.p. structure, have to be used with a proper consideration of electrons. We have derived two such conditions, satisfying the condition of rotational invariance, on the basis that the total pressure due to ions and electrons in the metal vanishes in the equilibrium.