Premium
A New Structural Model for Lithium Niobate
Author(s) -
Vyas J. C.,
Kothiyal G. P.,
Ghosh B.,
Gupta M. K.
Publication year - 1995
Publication title -
crystal research and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.377
H-Index - 64
eISSN - 1521-4079
pISSN - 0232-1300
DOI - 10.1002/crat.2170300216
Subject(s) - maxima and minima , lithium niobate , ferroelectricity , octahedron , phase transition , dielectric , ion , position (finance) , lithium (medication) , phase (matter) , energy (signal processing) , condensed matter physics , field (mathematics) , materials science , mineralogy , chemistry , physics , mathematics , mathematical analysis , optoelectronics , quantum mechanics , medicine , finance , endocrinology , pure mathematics , economics
A new model based on the crystal field theory is proposed for LiNbO 3 . According to this the central position of the Nb ions in oxygen octahedra is energetically unstable leading to the splitting of the potential energy curve into the one having two equivalent off‐centered minima. The phase transition temperature T c is related to the average height of the barrier existing between these energy minima. The model explains satisfactorily some of the properties of LiNbO 3 in the paraelectric and ferroelectric phases, which were not fully understood by earlier models.