Decomposition of lanthanum hafnate at high pressures
Abstract
Our high pressure x-ray diffraction and Raman scattering studies on lanthanum hafnate (La2Hf2O7) establish that it decomposes into its constituent oxides beyond ∼18GPa . These results are supported by our first-principles total energy calculations. Raman scattering results also imply that the products of dissociation are in an amorphouslike state beyond 50 GPa but crystallize slowly upon release of pressure.
- Publication:
-
Physical Review B
- Pub Date:
- June 2008
- DOI:
- 10.1103/PhysRevB.77.214105
- Bibcode:
- 2008PhRvB..77u4105G
- Keywords:
-
- 61.50.Ks;
- 61.05.cp;
- 78.30.-j;
- 71.15.Mb;
- Crystallographic aspects of phase transformations;
- pressure effects;
- X-ray diffraction;
- Infrared and Raman spectra;
- Density functional theory local density approximation gradient and other corrections