We study the shift in the critical temperature Tc in binary mixtures in strong electric fields. In experiments we measure the nonlinear dielectric effect (NDE) in a mixture of nitrobenze and n-octane and calculate Piekaras factor. We find that the critical anomaly of Piekaras factor is a function of an electric field strength. We propose to explain this observation as a result of a downward shift of Tc, and this allows us to calculate (εTc/εE2) = (-22 ± 10) × 10-16 (K m2)/V2. In the theoretical part we amend Landau and Lifshitzs formula and show that the downward shift of T c can be estimated from a simple mean-field theory taking into account the linear and quadratic terms in an expansion of the constitutive relation μ(x) between the electric constant μ and mixture composition x.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry