A Nematic to Nematic Transformation Exhibited by a Rod-Like Liquid Crystal

TY - JOUR

T1 - A Nematic to Nematic Transformation Exhibited by a Rod-Like Liquid Crystal

AU - Mandle, Richard

AU - Cowling, Stephen James

AU - Goodby, John William

N1 - © the Owner Societies 2017.

PY - 2017/5/14

Y1 - 2017/5/14

N2 - A novel, highly polar rod-like liquid crystal was found to exhibit two distinct nematic mesophases (N and Nx). When studied by microscopy and X-ray scattering experiments, and under applied electric fields, the nematic phases are practically identical. However, calorimetry experiments refute the possibility of an intervening smectic mesophase, and the transformation between the nematic phases was associated with a weak thermal event. Analysis of measured dielectric data, along with molecular properties obtained from DFT calculations, applying the Maier-Meier relationship allowed for the degree of antiparallel pairing of dipoles in both nematic phases to be quantified. Based on the results, we conclude that the onset of the lower temperature phase is driven by the formation of antiparallel molecular associations.

AB - A novel, highly polar rod-like liquid crystal was found to exhibit two distinct nematic mesophases (N and Nx). When studied by microscopy and X-ray scattering experiments, and under applied electric fields, the nematic phases are practically identical. However, calorimetry experiments refute the possibility of an intervening smectic mesophase, and the transformation between the nematic phases was associated with a weak thermal event. Analysis of measured dielectric data, along with molecular properties obtained from DFT calculations, applying the Maier-Meier relationship allowed for the degree of antiparallel pairing of dipoles in both nematic phases to be quantified. Based on the results, we conclude that the onset of the lower temperature phase is driven by the formation of antiparallel molecular associations.

UR - http://www.scopus.com/inward/record.url?scp=85024503644&partnerID=8YFLogxK

U2 - 10.1039/C7CP00456G

DO - 10.1039/C7CP00456G

M3 - Article

SN - 1463-9076

VL - 19

SP - 11429

EP - 11435

JO - Physical Chemistry Chemical Physics

JF - Physical Chemistry Chemical Physics

IS - 18

M1 - 11429

ER -