skip to main content

Title: Theoretically informed Monte Carlo simulation of liquid crystals by sampling of alignment-tensor fields

A theoretically informed coarse-grained Monte Carlo method is proposed for studying liquid crystals. The free energy functional of the system is described in the framework of the Landau-de Gennes formalism. The alignment field and its gradients are approximated by finite differences, and the free energy is minimized through a stochastic sampling technique. The validity of the proposed method is established by comparing the results of the proposed approach to those of traditional free energy minimization techniques. Its usefulness is illustrated in the context of three systems, namely, a nematic liquid crystal confined in a slit channel, a nematic liquid crystal droplet, and a chiral liquid crystal in the bulk. It is found that for systems that exhibit multiple metastable morphologies, the proposed Monte Carlo method is generally able to identify lower free energy states that are often missed by traditional approaches. Importantly, the Monte Carlo method identifies such states from random initial configurations, thereby obviating the need for educated initial guesses that can be difficult to formulate.
Authors:
;  [1] ;  [2] ;  [3] ;  [4] ;  [1] ;  [4]
  1. Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637 (United States)
  2. Departamento de Física, Universidad Autónoma Metropolitana, Iztapalapa, DF 09340, México (Mexico)
  3. Departamento de Materiales y Minerales, Universidad Nacional de Colombia, Sede Medellín, Medellín (Colombia)
  4. (United States)
Publication Date:
OSTI Identifier:
22493443
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 143; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALIGNMENT; APPROXIMATIONS; CHIRALITY; COMPARATIVE EVALUATIONS; COMPUTERIZED SIMULATION; DROPLETS; FINITE DIFFERENCE METHOD; FREE ENERGY; LIQUID CRYSTALS; MINIMIZATION; MONTE CARLO METHOD; MORPHOLOGY; RANDOMNESS; SAMPLING; STOCHASTIC PROCESSES; TENSOR FIELDS