Theory of the vibrational spectra of transition h.c.p. metals

Abstract

A semi-first principle (SFM) model using the concept of a rigid-shell moving relative to its nucleus to simulate the response of the d-electrons has been proposed for studying lattice dynamics of transition metals which belong to the h.c.p. structure. The long-range interaction between ion-ion as well as shell-shell via conduction electrons is described using the screened potential and the short-range interaction is described using two-body and three-body unpaired forces between cores as well as shells. Elastic constants, phonon dispersion curves and thermal properties, e.g. lattice specific heat, Debye characteristic temperature of three prominent transition metals (Zr, Hf, Ti) have been calculated and compared with the experimental results. © 1989 Società Italiana di Fisica.