With the aim of possible application of nematic liquid crystals in microwave devices with non-linear characteristics, studies were carried out of their electrophysical properties under stationary and microwave electric fields. Liquid crystals (LC) are similar to ordinary liquids in their rheological properties, while their electric, magnetic, optical and other properties are similar to solid crystals. In this work, we studied nematic liquid crystals (NLC) of two chemical classes: 5CB - a typical representative of cyanobiphenyls (ε‖ = 19.9, ε⊥ = 6.9, Δε = 13) and ZhK-440 - a mixture of azoxy compounds (ε‖ = 4.9, ε⊥ = 5.25, Δε = - 0.35) [1]. The notation commonly used in LC science includes: ε,σ - dielectric permittivity and conductivity, ε‖, σ‖- dielectric permittivity and conductivity of LC in the direction of predominant orientation of long molecular axes (along the director) ε⊥, σ⊥- in the direction perpendicular to the director; Δε = ε‖ - ε⊥ and Δσ = σ‖ - σ⊥^s(or σ‖/σ⊥) are the measure of the anisotropy of dielectric permittivity and conductivity [2].
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