Phase transitions of Zn0.84Fe0.16Se under high-pressure

Abstract

The energy-dispersive X-ray-diffraction (EDXD) and Raman spectroscopy were employed to study the pressure induced phase transitions of Zn0.84Fe0.16Se crystal up to 21.0 and 32.0 GPa, respectively. A semiconductor-metal transition was identified by EDXD and Raman spectroscopic methods at 11.4 +/- 0.5 GPa. Other two phase transitions were found only in the Raman scattering study below 11.4 GPa. In addition, three unidentified Raman peaks were still observable above the metallization pressure. The existence of Fe impurity in the ZnSe up to a concentration of 0.16 reduced prominently the semiconductor-metal phase transition pressure. For Raman works, the three unidentified Raman peaks of Zn0.84Fe0.16Se above 10.9 GPa are possibly the TO modes in the thin surface of the high pressure metallic phase. (C) 1998 Elsevier Science Ltd. All rights reserved.