Abstract
A systematic approach to study the phase stability of based on ab initio calculations is presented. Three thermodynamically stable phases are identified and a new phase of symmetry is proposed for the first time for a complex hydride. The x-ray diffraction pattern and vibrational spectra of the structure agree well with recently reported experimental data on . Calculations of the free energy at finite temperatures suggest that the experimentally proposed phase is unstable at .
- Received 26 February 2004
DOI:https://doi.org/10.1103/PhysRevLett.93.145501
©2004 American Physical Society