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Simultaneous calculation of the helical pitch and the twist elastic constant in chiral liquid crystals from intermolecular torques

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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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Official URL: http://dx.doi.org/10.1063/1.1475747

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

Official Date:

1 June 2002

Dates:

Date	Event
1 June 2002	Published

Volume:

Vol.116

Number:

No.21

Page Range:

pp. 9422-9430

Identifier:

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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