Lattice Dynamics of Magnesium Using a Pseudopotential Approach

Abstract

The lattice dynamics of hexagonal closed-packed metals is discussed using the pseudopotential approach of Harrison. Explicit expressions for the elements of the dynamical matrix are obtained and numerical calculations are made for the phonon dispersion relations along the [0001] and [$01\overline{1}0$] directions in magnesium, using the results previously obtained by Harrison from a first-principles calculation. Comparison with the experimental data of Iyengar et al., however, shows poor agreement. Calculations are also made using a two-parameter-model pseudopotential proposed by Harrison, which shows better agreement with experiment.