https://doi.org/10.1140/epjp/s13360-021-01639-x
Regular Article
Ab initio investigation in PbZrO
antiferroelectric: structural and vibrational properties
1
Laboratoire de Physique des Solides et des Interfaces, Institut Supérieur Pédagogique de Bukavu, Bukavu, Democratic Republic of the Congo
2
Physique Théorique des Matériaux, Université de Liège, B-4000, Sart Tilman, Belgium
Received:
13
January
2021
Accepted:
3
June
2021
Published online:
14
June
2021
Using first-principles calculations, we investigate the structural and vibrational properties of PbZrO. Starting from the high-symmetry cubic perovskite phase, for which the phonon dispersion curves are reported to have many unstable branches, we identify some key intrinsic characteristics allowing the prediction of materials with the propensity of developing an antiferroelectric behavior. We confirm the key role that R antiferrodistortive modes play in condensing the observed antiferroelectric phase, via a cooperative bilinear coupling, and the nearest with the ferroelectric state. Our work shows that, given all their important potential wells none of the individual modes condensed deletes all other and that it is their coupling which plays a key role in the condensation of the ground state lead zirconate, and these couplings would explain why Pbam and R3c phases are close in energy for promoting the first-order transition.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2021
