Lattice dynamical calculation of isotropic negative thermal expansion in ZrW2O8 over 0-1050 K

Citation
R. Mittal et Sl. Chaplot, Lattice dynamical calculation of isotropic negative thermal expansion in ZrW2O8 over 0-1050 K, PHYS REV B, 60(10), 1999, pp. 7234-7237
Citations number
20
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B-CONDENSED MATTER
ISSN journal
01631829 → ACNP
Volume
60
Issue
10
Year of publication
1999
Pages
7234 - 7237
Database
ISI
SICI code
0163-1829(19990901)60:10<7234:LDCOIN>2.0.ZU;2-9
Abstract
We report detailed lattice dynamical calculations of the large isotropic ne gative thermal expansion (NTE) over 0-1050 K in ZrW2O8 in its cubic phase. The results bring out the unusually dominant quantitative contributions to NTE of the transverse acoustic, and librational and translational optic pho nons below 8 meV. The contributions of these phonons are reduced in the hig h pressure orthorhombic phase which therefore shows NTE only below 270 K. T he calculations show a fair agreement with the published thermal expansion data in both phases. [S0163-1829(99)14233-3].