Phase transitions in PbTe under quasi-hydrostatic pressure up to 50 GPa
Abstract
PbTe has been investigated using synchrotron X-ray diffraction (XRD) in a diamond anvil cell under quasi-hydrostatic pressures up to 50 GPa. Upon compression to 6.6 GPa, the initial NaCl phase transforms to an intermediate phase, which is confirmed to be an orthorhombic structure with a space group Pnma. At 18.4 GPa, the intermediate Pnma phase undergoes a phase transition to the CsCl structure. The systemic analysis of the crystal structures between the NaCl and intermediate phases indicates that the structure of the Pnma phase could be derived from the distortion of the NaCl structure. The bulk modulus of the CsCl phase is B0=52(2) GPa with V0=60.8(4) Å3 and B‧0=4.0 (fixed), slightly larger than the NaCl phase (B0=44(1) GPa) and the intermediate phase (B0=49(3) GPa).
- Publication:
-
High Pressure Research
- Pub Date:
- December 2013
- DOI:
- 10.1080/08957959.2013.848278
- Bibcode:
- 2013HPR....33..713L
- Keywords:
-
- PbTe;
- high pressure;
- diamond anvil cell;
- phase transition