Sulfur-linked cyanoterphenyl-based liquid crystal dimers and the twist-bend nematic phase

Physical Chemistry Chemical Physics, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

The synthesis and characterisation of two series cyanoterphenyl-based liquid crystal dimers containing sulfur links between the spacer mesogenic units, 34-{ω-[(4'-cyano-[1,1'-biphenyl]-4-yl)thio]alkyl}-[11,21:24,31-terphenyl]-14-carbonitriles (CBSnCT), 34-({ω-[(4'-cyano-[1,1'-biphenyl]-4-yl)thio]alkyl}oxy)-[11,21:24,31-terphenyl]-14-carbonitriles (CBSnOCT) are described. odd members both show twist-bend nematic phases, whereas even exhibit only phase. This is consistent with widely held view that molecular curvature a prerequisite for observation nematic-isotropic nematic-nematic transition temperatures higher cyanoterphenyl groups than corresponding cyanobiphenyl-based dimers. change more pronounced attributed to enhanced interaction strength parameter associated fragment shapes, as governed by spacer, rather similar. behaviour CBS2CT appears somewhat anomalous exhibits value temperature expected, this presence highly bent conformations.

Language: Английский

Mesogenic cholesterol-naphthalene dimers: Synthesis, characterization, mesogenic properties, photochromic behaviour and theoretical insights

Journal of Molecular Liquids, Journal Year: 2024, Volume and Issue: unknown, P. 126296 - 126296

Published: Oct. 1, 2024

Language: Английский