Thermodynamic model for electro-optical properties of antiferroelectric phase in mesogen W-330-3 and W-331-3

ABSTRACT

A thermodynamic model developed by our group has been employed to explore the electro-optical properties of the chiral antiferroelectric smectic C (Sm $C_A^{\ast }$) phase. In the present study, the temperature dependence of tilt angle and spontaneous polarization of binary ferroelectric mixtures represented as W-330-3 and W-331-3 exhibiting ferroelectric Sm C* and antiferroelectric Sm $C_A^{\ast }$ phase has been investigated. Within the framework of this model, the free-energy density characterizing the system featuring the Sm $C_A^{\ast }$ phase is expressed as a series expansion that incorporates all pertinent degrees of freedom: tensor orientational order ${\mathbf{Q}}_{\mathbf{ij}}$, scalar smectic order ψ, polarization vector P, wave vector q of the helix and the resulting coupling terms between these order parameters. The values of Landau coefficients featured in the expansion series are derived from experimental data (tilt angle and spontaneous polarization) of W-330-3 and W-331-3. A substantial agreement between the theoretical predictions and experimental observations has been found.

KEYWORDS:

• Antiferroelectric liquid crystal
• free energy density expansion
• spontaneous polarizations
• order parameters
• structural properties
• electro-optical properties

Acknowledgments

I would like to acknowledge JSSMVP Mysore for kind support and encouragement.

Disclosure Statement

No potential conflict of interest was reported by the author(s).