Investigation of The Biased Rotation of Chiral Molecule Around its Long Molecular Axis in the Ferroelectric Liquid Crystal Mixture

Abstract

Spontaneous polarization (P_s), tilt angle (θ), helical pitch (p) and densytometric (ρ) characteristics versus temperature and concentration of chiral dopant have been measured for FLC mixture. On the base of computer modelling the molecular dipole moment (μ), transverse (α_t) and longitudinal (α₁) molecular polarizabilities as well as angle (γ and Φ₀) between the vector μ and main long n and short 1 molecular axes of inertia have been calculated. Knowing the molecular parameters μ, α_t, α_l, γ and Φ₀ and state parameters θ, p, spontaneous polarization P_s has been calculated as the vector sum of the components of molecular dipole moment μ₁ perpendicular to the tilt direction. To do it the Zeks¹ rotational potential modified by us² has been used. After comparing spontaneous polarization P_s taken from experimental and obtained from theoretical approximation the biased rotation parameter η has been calculated.