Pseudo-molecular approach for the elastic constants of nematic liquid crystals interacting via anisotropic dispersion forces

• Published in: Physics letters. A 2014-01, Vol.378 (4), p.453-458
• Main Authors: Simonário, P.S., Freire, F.C.M., Evangelista, L.R., Teixeira-Souza, R.T.
• Format: Article
• Language: English
• Subjects: Anisotropy; Dispersions; Eccentricity; Elastic constants; Lattice models; Liquid crystals; Mathematical analysis; Nematic; Solid state physics
• ISSN: 0375-9601; 1873-2429
• DOI: 10.1016/j.physleta.2013.12.020

The bulk and the surface-like elastic constants of a nematic liquid crystal are calculated for an ensemble of particles interacting via anisotropic dispersion forces using the pseudo-molecular method. The geometrical anisotropy of the molecules is also taken into account in the calculations by choosing a molecular volume of ellipsoidal shape. Analytical expressions for the elastic constants are obtained as a function of the eccentricity in the molecular volume shape. The method allows one to explore the dependence on the molecular orientation with respect to the intermolecular vector by analyzing the magnitude and the behaviour of macroscopic elastic parameters defining the nematic phase. •Liquid crystals elastic constants are calculated for anisotropic dispersion forces.•The Pseudo-molecular method furnishes analytical expressions of elastic constants.•The interaction and molecular volume are of ellipsoidal shape.•Bulk and surface-like elastic constants depend on the molecular volume shape.•Surface-like elastic constants become negative for a small region of parameters.