Determination of the temperature dependence of lattice parameters in ferroelastics at 4/mF2/m phase transition

ABSTRACT

Method of determining temperature dependence of lattice parameters and crystal cell volume of ferroelastics in analytical form at 4 / m F 2 / m structural phase transition has been suggested on the basis of conservation condition of paraelastic phase macrosymmetry in a polydomain crystal. The analysis of functions for the sample of BiVO₄ was made. Temperature dependence of the spontaneous strain components and crystallographic axes spontaneous rotation are determined for the crystal.

KEYWORDS:

• Ferroelastics
• temperature dependence
• lattice parameters
• BiVO₄

Acknowledgment

We wish to thank Prof. I.G. Wood for the experimental data on temperature dependence of lattice parameter in BiVO₄.