Ferroelectric nematic phase in the system of perfectly aligned cylindrically symmetric rods

ABSTRACT

The recent experimental discovery of ferroelectric and splay nematic phases has sparked interest in comprehending the crucial molecular features necessary to stabilise these innovative structures. This study advances the ongoing discourse by investigating the significance of both molecular elongation and the distribution of molecular dipoles along the main molecular axis. Using Density Functional Theory, we have established that a molecular shape characterised by cylindrical symmetry and the presence of strong parallel dipoles along the symmetry axis can lead to the self-assembly of a ferroelectric nematic, which is more stable than the conventional uniaxial nematic phase. Additionally, for simple $D_{\mathrm{\infty }\mathit{h}}$-symmetric shapes and two dipoles per molecule we provide criteria for achieving an optimal dipole distribution along the molecular axis.

GRAPHICAL ABSTRACT

KEYWORDS:

• Liquid crystals
• ferroelectric nematic phase
• Onsager theory
• ground state analysis

Disclosure statement

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

Additional information

Funding

This work was supported by Grant No. [DEC-2021/43/B/ST3/03135] of the National Science Centre in Poland.