Abstract:
We have studied the electron concentration and pressure induced-structural transitions in solid solutions In(1-x) Cd(x) (0 < x < 0.1), and In(1-x) Sn(x) (0 < x < 0.2) by means of first-principles calculations. At ambient pressure the structural sequence face-centered cubic (fcc) to body-centered tetragonal (c/a > sqr(2) (bct-I) to body-centered tetragonal (c/a < sqr(2) (bct-II) is realized with increasing of valence electron concentration (VEC). High pressure has the same effect as the increase of electron concentration shifting the occurrence of the structural transitions to lower valence electron concentration. The driving force behind the peculiar structural sequence is an enhancement of s-p hybridization with increasing VEC. Our results demonstrates very good agreement with available experimental data.