Germano, Guido, Allen, M. P. and Masters, Andrew J.. (2002) Simultaneous calculation of the helical pitch and the twist elastic constant in chiral liquid crystals from intermolecular torques. Journal of Chemical Physics, Vol.116 (No.21). pp. 9422-9430. ISSN 0021-9606

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Abstract

We present a molecular simulation method that yields simultaneously the equilibrium pitch wave number q and the twist elastic constant K2 of a chiral nematic liquid crystal by sampling the torque density. A simulation of an untwisted system in periodic boundary conditions gives the product K2q; a further simulation with a uniform twist applied provides enough information to separately determine the two factors. We test our new method for a model potential, comparing the results with K2q from a thermodynamic integration route, and with K2 from an order fluctuation analysis. We also present a thermodynamic perturbation theory analysis valid in the limit of weak chirality.

Item Type:	Journal Article
Subjects:	Q Science > QC Physics
Divisions:	Faculty of Science > Physics
Library of Congress Subject Headings (LCSH):	Liquid crystals, Thermodynamics
Journal or Publication Title:	Journal of Chemical Physics
Publisher:	American Institute of Physics
ISSN:	0021-9606
Date:	1 June 2002
Volume:	Vol.116
Number:	No.21
Page Range:	pp. 9422-9430
Identification Number:	10.1063/1.1475747
Status:	Peer Reviewed
Access rights to Published version:	Open Access
Funder:	Leverhulme Trust (LT), Engineering and Physical Sciences Research Council (EPSRC), British Council
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URI:	http://wrap.warwick.ac.uk/id/eprint/354

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