Ab initio phonon dispersion curves and interatomic force constants of barium titanate
| dc.creator | Ghosez, Ph. | |
| dc.creator | Gonze, X. | |
| dc.creator | Michenaud, J. -P. | |
| dc.date | 1997-06-30 | |
| dc.date.accessioned | 2026-07-07T09:11:52Z | |
| dc.date.available | 2026-07-07T09:11:52Z | |
| dc.description | The phonon dispersion curves of cubic BaTiO_3 have been computed within a first-principles approach and the results compared to the experimental data. The curves obtained are very similar to those reported for KNbO_3 by Yu and Krakauer [Phys. Rev. Lett. 74, 4067 (1995)]. They reveal that correlated atomic displacements along <100> chains are at the origin of the ferroelectric instability. A simplified model illustrates that spontaneous collective displacements will occur when a dozen of aligned atoms are coupled. The longitudinal interatomic force constant between nearest neighbour Ti and O atoms is relatively weak in comparison to that between Ti atoms in adjacent cells. The small coupling between Ti and O displacements seems however necessary to reproduce a ferroelectric instability. | |
| dc.description | 12 pages, 4 figures | |
| dc.identifier | https://arxiv.org/abs/cond-mat/9706294 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/9706294 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/151835 | |
| dc.subject | Materials Science | |
| dc.title | Ab initio phonon dispersion curves and interatomic force constants of barium titanate | |
| dc.type | text |