Liquid Crystal Lattice Models on Quadrics Supercomputers

The implementation of a Monte Carlo code for simulations of liquid crystal lattice models on the Quadrics massively parallel SIMD supercomputer is described. The use of a Quadrics with 512 processors is proving essential in studying the nematic–isotropic phase transition to an unprecedented level of accuracy using more than 106 particles. Here some tests on the Lebwohl–Lasher model with and without an applied field are presented.

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A study of the nematic–isotropic phase transition in liquid crystals by monte carlo simulations of lattice models

Journal of Physical Studies ◽

10.30970/jps.01.232 ◽

1997 ◽

Vol 1 (2) ◽

pp. 232-240

Author(s):

Ja. M. Ilnytskyi

Keyword(s):

Phase Transition ◽

Monte Carlo ◽

Liquid Crystals ◽

Monte Carlo Simulations ◽

Lattice Models ◽

Isotropic Phase

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THREE-DIMENSIONAL VISUALIZATION OF MOLECULAR ORGANIZATION AND PHASE TRANSITIONS IN LIQUID CRYSTAL LATTICE MODELS

International Journal of Modern Physics C ◽

10.1142/s012918319200083x ◽

1992 ◽

Vol 03 (06) ◽

pp. 1209-1220 ◽

Cited By ~ 2

Author(s):

CESARE CHICCOLI ◽

PAOLO PASINI ◽

FRANCO SEMERIA ◽

CLAUDIO ZANNONI

Keyword(s):

Monte Carlo ◽

Liquid Crystal ◽

Crystal Lattice ◽

Personal Computer ◽

Three Dimensional ◽

Lattice Models ◽

Point Of View ◽

Molecular Organization ◽

Computer Visualization ◽

Physical Information

An example of three-dimensional animation of Monte Carlo simulation results of liquid crystal lattice models is presented. Molecular configurations are obtained from Monte Carlo simulations on a VAX cluster and downloaded to a 486 personal computer. Visualization of molecular organizations and of their change at a phase transition is obtained by suitable colour coding of orientations and of other relevant physical information on the personal computer, and recorded on a VHS system using a genlock card. The animation sequences generated have a twofold interest: they are useful for educational purposes and, from a scientific point of view, they provide a tool for exploring a large amount of data and investigating the phenomena under study in a non-numerical way.

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Dissipative structures induced by photoisomerization in a dye-doped nematic liquid crystal layer

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2017.0382 ◽

2018 ◽

Vol 376 (2135) ◽

pp. 20170382 ◽

Cited By ~ 1

Author(s):

I. Andrade-Silva ◽

U. Bortolozzo ◽

C. Castillo-Pinto ◽

M. G. Clerc ◽

G. González-Cortés ◽

...

Keyword(s):

Phase Transition ◽

Liquid Crystal ◽

Nematic Liquid Crystal ◽

Dissipative Structures ◽

Input Power ◽

Isotropic Phase ◽

Crystal Layer ◽

Liquid Crystal Layer ◽

Nematic Liquid Crystal Layer ◽

Interface Propagation

Order–disorder phase transitions driven by temperature or light in soft matter materials exhibit complex dissipative structures. Here, we investigate the spatio-temporal phenomena induced by light in a dye-doped nematic liquid crystal layer. Experimentally, for planar anchoring of the nematic layer and high enough input power, photoisomerization processes induce a nematic–isotropic phase transition mediated by interface propagation between the two phases. In the case of a twisted nematic layer and for intermediate input power, the light induces a spatially modulated phase, which exhibits stripe patterns. The pattern originates as an instability mediated by interface propagation between the modulated and the homogeneous nematic states. Theoretically, the phase transition, emergence of stripe patterns and front dynamics are described on the basis of a proposed model for the dopant concentration coupled with the nematic order parameter. Numerical simulations show quite a fair agreement with the experimental observations. This article is part of the theme issue ‘Dissipative structures in matter out of equilibrium: from chemistry, photonics and biology (part 2)’.

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