# Molecular shape and flexoelectricity

@article{Billeter1999MolecularSA, title={Molecular shape and flexoelectricity}, author={Jeffrey Lee Billeter and Robert A. Pelcovits}, journal={Liquid Crystals}, year={1999}, volume={27}, pages={1151 - 1160} }

Monte Carlo simulations were performed of systems of wedge-shaped objects formed from Gay-Berne ellipsoids joined to Lennard-Jones spheres. We studied two different wedge shapes, one more asymmetric than the other. The bend and splay flexoelectric coefficients were measured in the isotropic and smectic phases using linear response theory, and found to be negligibly small in the isotropic phase. We found a close connection between the properties of the intermolecular potential and the…

## 17 Citations

### Shape model for the molecular interpretation of the flexoelectric effect.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2001

A mean-field model for the flexoelectric polarization in nematics is presented, based on a continuous description of director deformations coupled to the molecular degrees of freedom via surface interactions, which provides numerical estimates of the effect and its temperature dependence and allows the recognition of the relevant molecular features for its emergence.

### Dipolar interactions, molecular flexibility, and flexoelectricity in bent-core liquid crystals.

- PhysicsThe Journal of chemical physics
- 2005

The effects of dipolar interactions and molecular flexibility on the structure and phase behavior of bent-core molecular fluids are studied using Monte Carlo computer simulations. Some calculations…

### Statistical theory of the flexoelectric polarization for the uniaxial nematic phase.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2007

It is shown that, for wedge-shaped polar molecules, the FE coefficients are proportional to the longitudinal component of the molecule dipole moment.

### Flexoelectric effect modelling

- Physics
- 2008

A statistical theory of dipole flexoelectric (FE) polarization in liquid crystals is used to calculate temperature dependence of order parameters, elastic constants and FE coefficients. Two systems…

### Calculation of flexoelectric coefficients for a nematic liquid crystal by atomistic simulation.

- Chemistry, PhysicsThe Journal of chemical physics
- 2004

Equilibrium molecular dynamics calculations have been performed for the liquid crystal molecule n-4-(trans-4-n-pentylcyclohexyl)benzonitrile (PCH5) using a fully atomistic model and values of e(s) and e(b) calculated from simulation are consistent with those found from experiment.

### Molecular simulation and theory of liquid crystals: chiral parameters, flexoelectric coefficients, and elastic constants

- Chemistry
- 2001

We present an overview of the simulation methods available to calculate the phenomenological coefficients which appear in the Frank free energy of nematic liquid crystals: the elastic constants,…

### Computer simulations of hard pear-shaped particles.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2003

Results obtained from Monte Carlo simulations investigating mesophase formation in two model systems of hard pear-shaped particles show isotropic, nematic and, unusual for a hard-particle model, interdigitated smectic A2 phases.

### Liquid crystal phases of achiral banana-shaped molecules: a computer simulation study

- Physics
- 2002

The phase behaviour of achiral banana-shaped molecules was studied by computer simulation. The banana-shaped molecules were described by model intermolecular interactions based on the Gay-Berne…

### Flexoelectric polarization in the biaxial nematic phase.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2008

The dipole flexoelectric (FE) polarization in liquid crystals is derived in the thermodynamic limit at small distortions and small density. General microscopic expressions for the FE coefficients are…

### On the threshold characteristics of the flexoelectric domains arising in a homogeneous electric field: The case of anisotropic elasticity

- PhysicsThe European physical journal. E, Soft matter
- 2010

Computer calculations for a planar nematic layer with anisotropic elasticity and both negative and positive dielectric anisotropy under the action of a homogeneous flexoelectrically deforming d.c. electric field allow a selection of particular values of physical parameters, in order to improve the performance of devices exploitingflexoelectrcity in nematics.

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