Abstract
We present a model of ferroelectrics which takes into account the softening of a transverse optical mode, the existence of dynamical spontaneous off-center displacements and their interaction with each other. In this paper we confine ourselves to temperatures above Tc. The model is quantitatively compared with experimental results in two very different materials, PbTiO3 and KNbO3. The results show that the existence of off-center displacements and their interaction with the soft mode play a crucial role in explaining the properties of ferroelectric phase transitions in perovskite crystals and possibly other crystal families.
Original language | English |
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Pages (from-to) | 425-430 |
Number of pages | 6 |
Journal | Solid State Communications |
Volume | 103 |
Issue number | 7 |
DOIs | |
State | Published - Aug 1997 |
Keywords
- A. Ferroelectrics
- C. EXAFS
- D. Phase transitions