UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Chiral power change upon photoisomerization in twisted nematic liquid crystals

Simoncelli, S; Aramendia, PF; (2015) Chiral power change upon photoisomerization in twisted nematic liquid crystals. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy , 142 pp. 94-100. 10.1016/j.saa.2015.01.072. Green open access

[thumbnail of SAA-D-14-02638R1.pdf]
Preview
Text
SAA-D-14-02638R1.pdf - Accepted Version

Download (972kB) | Preview

Abstract

In this work, we use the photoisomerization of azobenzenes, a phenanthrospirooxazine, and a fulgide in a twisted nematic liquid crystalline phase to change the chiral twisting power of the system. The changes are probed by the rotatory power of linearly polarized light. Time resolved and steady state experiments are carried out. The chiral change and the photoisomerization process have similar characteristic recovery times and activation energy, thus probing that the change is induced by the modification in the chemical composition of the photochromic dopant system. The amplitude of the light twisting power change correlates with the order change in the liquid crystal (LC) but not with the modification in the absorption characteristics of the system. This indicates that the driving force of the chiral change is the microscopic order modification in the LC phase that affects the helical pitch of the phase.

Type: Article
Title: Chiral power change upon photoisomerization in twisted nematic liquid crystals
Open access status: An open access version is available from UCL Discovery
DOI: 10.1016/j.saa.2015.01.072
Publisher version: https://doi.org/10.1016/j.saa.2015.01.072
Language: English
Additional information: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
UCL classification: UCL
UCL > Provost and Vice Provost Offices > UCL BEAMS
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences
UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > London Centre for Nanotechnology
URI: https://discovery.ucl.ac.uk/id/eprint/10089461
Downloads since deposit
107Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item