Phonons and martensitic phase transitions in disordered Li−Mg alloys

We present a calculation of the phonon spectra and of the martensitic transition temperature for the bcc»hcp transformation in Li–Mg alloys. The treatment is based ona. pseudopotential-derived interatomic forces,b. a cluster relaxation technique for determining the static distortions of the mean crystal lattice in a substitutional alloy, andc. a recursion method for calculating the spectral functions and vibrational densities of state. We report that the observed variation of the martensitic temperature with concentration results from a delicate interplay of electronic and vibrational effects.This work was supported by the Jubiläumsfonds der Österreichischen Nationalbank under project no. 2141