2010/07/30 by Peng Zhang, Bao‐Tian Wang, Zhang, Peng +5
Materials Science · Physics and Astronomy · #FOS: Physical sciences #Hydrogen Storage and Materials #Materials Science (cond-mat.mtrl-sci) #Nuclear Materials and Properties #Superconductivity in MgB2 and Alloys
paper · pdf · doi:10.48550/arxiv.1007.5392
openalex publication_date 2010/07/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Structural, mechanical, electronic, and thermodynamic properties of fluorite and tetragonal phases of ZrH2 are systematically studied by employing the density functional theory within generalized gradient approximation. The existence of the bistable structure for ZrH2 is mainly due to the tetragonal distortions. And our calculated lattice constants for the stable face-centered tetragonal (fct) phase with c/a=0.885 are consistent well with experiments. Through calculating elastic constants, the mechanically unstable characters of face-centered cubic (fcc) phase and fct structure with c/a=1.111 are predicted. As for fct0.885 structure, our calculated elastic constants explicitly indicate that it is mechanically stable. Elastic moduli, Poisson's ratio, and Debye temperature are derived from elastic constants. After analyzing total and partial densities of states and valence electron charge distribution, we conclude that the Zr-H bonds in ZrH2 exhibit weak covalent feature. But the ionic property is evident with about 1.5 electrons transferring from each Zr atom to H. Phonon spectrum results indicate that fct0.885 and fct1.111 structures are dynamically stable, while the fcc structure is unstable.