Structural, electronic, elastic, and piezoelectric properties of α -quartz and M X O 4 ( M = Al , Ga, Fe; X = P , As) isomorph compounds: A DFT study

Pierre Labéguerie , Moussab Harb (1, 2, 3) , Isabelle Baraille (4) , Michel Rérat (4)

1 IPNL - Institut de Physique Nucléaire de Lyon
2 IRCELYON - Institut de recherches sur la catalyse et l'environnement de Lyon
3 CATREN - IRCELYON-Catalyse Hétérogène pour la Transition Energétique
4 IPREM - Institut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux

We report the structural, electronic, elastic, and piezoelectric properties of some ␣-quartz SiO 2 isotypes, namely, AlPO 4 , GaPO 4 , GaAsO 4 , and FePO 4. This family of crystals is well known for its elastic and piezoelectric properties related to their MO 4 and XO 4 tetrahedral units, especially the M-OX bridging angle and the tilt angle ␦, the most distorted structures being expected to exhibit the highest piezoelectric coupling constant. We have then computed the optimized structure of each MXO 4 isomorph compound in order to study the variation in the elastic and piezoelectric tensors with respect to and ␦. A comparison between our results at the density-functional theory level and the available data ͑theoretical and experimental ones͒ has been made. The differences observed for the whole class of systems has been discussed and a comparison with the SiO 2 ␣-quartz behavior is made.

Domains: Theoretical and/or physical chemistry; Material chemistry; Analytical chemistry

Pierre Labéguerie, Moussab Harb, Isabelle Baraille, Michel Rérat. Structural, electronic, elastic, and piezoelectric properties of α -quartz and M X O 4 ( M = Al , Ga, Fe; X = P , As) isomorph compounds: A DFT study. Physical Review B, 2010, 81 (4), ⟨10.1103/PhysRevB.81.045107⟩. ⟨hal-03227499⟩