Ab initio phonon dispersion curves and interatomic force constants of barium titanate

Ph Ghosez, X. Gonze, J. P. Michenaud

Результат исследований: Вклад в журналСтатья конференциирецензирование

83 Цитирования (Scopus)


The phonon dispersion curves of cubic BaTiO3 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 KNbO3 by Yu and Krakauer. 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 linear ferroelectric instability.

Язык оригиналаАнглийский
Страницы (с-по)205-217
Число страниц13
Номер выпуска1 -4; 1-2
СостояниеОпубликовано - 1998
Опубликовано для внешнего пользованияДа
СобытиеProceedings of the 1997 Williamsburg Workshop on Ferroelectrics - Williamsburg, VA, USA
Продолжительность: 2 февр. 19975 февр. 1997


Подробные сведения о темах исследования «Ab initio phonon dispersion curves and interatomic force constants of barium titanate». Вместе они формируют уникальный семантический отпечаток (fingerprint).