High-pressure behavior of CdSb: Compound decomposition, phase formation, and amorphization

High pressure study of the binary CdSb compound reveal several phase transitions including compound decomposition, phase formation, and amorphization on decompression. Above 7.3 GPa a simple hexagonal (sh) phase of composition Cd44Sb56 and an excess of pure Cd are observed. Above 20 GPa after heating at 423 K, the material decomposes into nearly pure components, hcp-Cd and Sb-II. Above 40 GPa, a bcc phase (solid solution of Cd in bcc-Sb) is observed together with an additional intermediate phase. Amorphization of CdSb occurs on decompression after decomposition into the sh phase and Cd. Structural properties of the amorphous phase in the Cd-Sb system are compared with those of the known amorphous semiconductors and discussed in terms of Fermi sphere-Brillouin zone interactions.