The self-consistent ab initio lattice dynamical method

We describe a method for calculating temperature dependent phonon spectra self consistently from first principles. The method combines concepts from Born’s self-consistent phonon approach with ab initio calculations of accurate interatomic forces in a supercell. Test calculations on the high temperature bcc phase of Ti, Zr, Hf, Sc and Y, as representative examples, reproduce the observed high temperature phonon frequencies with good accuracy. By use of an embedded atom potential we demonstrate the method’s relevance in calculating approximate critical temperatures of solid–solid phase transitions for the hcp to bcc transition in Zr.