Ehlectron-phonon interaction in indium-magnesium alloys with a structural phase transitions

Insub(1-x)Mgsub(x) alloys in the face-centered tetragonal phase are investigated by the electron single-particle tunneling technique. It is shown that the electron-phonon coupling constant lambda increases on approach to the face-centered tetragonal reversible face-centered cubic phase transition point xsub(m). The increase of lambda is due to both a growth of the electron state density at the Fermi level ν(epsilonsub(F)) and to the redistribution of phonon frequencies observed on the basis of the spectral functions of the electron-phonon interaction g(ω). It is suggested that the growth of ν(epsilonsub(F)) and deformation of g(ω) are due to the Lifshitz transition which occurs in the alloys at x approximately 0.02