Multiple polar and non-polar nematic phases

TL;DR

This paper reports on liquid crystal materials with up to three nematic phases, revealing diverse polar and non-polar orders, and demonstrates how molecular modifications can induce direct phase transitions.

Contribution

It introduces new liquid crystal materials with multiple nematic phases and explores how molecular structure influences phase behavior and transitions.

Findings

Lower temperature nematic phase is ferroelectric.

Highest temperature nematic phase is apolar.

Intermediate phase exhibits local antiferroelectric order.

Abstract

Liquid crystal materials exhibiting up to three nematic phases are reported. Dielectric response measurements show that while the lower temperature nematic phase has ferroelectric order and the highest temperature nematic phase is apolar, the intermediate phase has local antiferroelectric order. The modification of the molecular structure by increasing the number of lateral fluorine substituents leads to one of the materials showing a direct isotropic-ferronematic phase transition.