Structural transformations in the In5Bi3 compound under high pressure

The compound In5Bi3 decomposes at pressure 15 GPa and temperature 150degreesC into two phases of different compositions. Each phase represents a tetragonal distortion of the body-centred cubic phase, one with axial ratio c/a > 1 and the other with c/a < 1. These phases follow the Bain path-a tetragonal distortion of the cubic structure on the way from face-centred cubic to body-centred cubic, observed for tetragonal phases of In and Sn alloys as a function of composition (or electron concentration) at ambient and high pressure. Ambient-pressure stoichiometic compounds in the In-Bi alloy system are replaced under pressure by a sequence of metallic random phases with the structure determined by the electron concentration.