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In Silico Measurement of Elastic Moduli of Nematic Liquid Crystals

Journal Article · · Physical Review Letters
 [1];  [2];  [1]
  1. Univ. of Notre Dame, IN (United States). Dept. of Chemical and Biomolecular Engineering
  2. Univ. of Chicago, IL (United States). Inst. for Molecular Engineering; Argonne National Lab. (ANL), Argonne, IL (United States)
Experiments on confined droplets of the nematic liquid crystal 5CB have questioned long-established bounds imposed on the elastic free energy of nematic systems. This elasticity, which derives from molecular alignment within nematic systems, is quantified through a set of moduli which can be difficult to measure experimentally and, in some cases, can only be probed indirectly. This is particularly true of the surfacelike saddle-splay elastic term, for which the available experimental data indicate values on the cusp of stability, often with large uncertainties. Here, we demonstrate that all nematic elastic moduli, including the saddle-splay elastic constant k24, may be calculated directly from atomistic molecular simulations. Importantly, results obtained through in silico measurements of the 5CB elastic properties demonstrate unambiguously that saddle-splay elasticity alone is unable to describe the observed confined morphologies.
Research Organization:
Argonne National Laboratory (ANL), Argonne, IL (United States)
Sponsoring Organization:
National Science Foundation (NSF); U.S. Department of Defense (DOD) - Department of the Army; USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Science - Office of Basic Energy Sciences - Materials Sciences and Engineering Division - Midwest Integrated Center for Computational Materials (MICCoM)
Grant/Contract Number:
AC02-06CH11357
OSTI ID:
1459901
Alternate ID(s):
OSTI ID: 1425231
Journal Information:
Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 10 Vol. 120; ISSN 0031-9007
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

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Cited By (6)

Programming emergent symmetries with saddle-splay elasticity journal November 2019
Self-assembly of semiflexible polymers confined to thin spherical shells journal January 2018
Molecular simulations of analyte partitioning and diffusion in liquid crystal sensors journal January 2020
Novel elastic response in twist-bend nematic models journal January 2019
Nematic order in solutions of semiflexible polymers: Hairpins, elastic constants, and the nematic-smectic transition journal November 2018
Influence of the saddle-splay term on nematic liquid crystals confined between two coaxial cylinders journal May 2019

Figures / Tables (3)


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