Theoretical Study of Nematic to Isotropic Transition in Porous Media

• Authors: A. Govind , Kumarii Banerjee
• Languages of publication: EN

Abstracts

EN

Experimental observations show that the N-I transition temperature (T_{NI}) for liquid crystals embedded in solid porous materials is lower compared to that of the bulk liquid crystals and T_{NI} is reduced linearly with the inverse pore diameter. To explain this, various theoretical studies have been proposed. We propose to use the mean field approach. We modify the Maier-Saupe mean field theory to include the disordering effects of porosity as a disordering surface potential. A molecule near the surface is assumed to feel the mean field potential (the Maier-Saupe type) and also the surface induced potential. We calculate the values of the nematic order parameter and hence find the T_{NI} for different pore diameters. The weighted average of the order parameter is calculated considering the cylindrical symmetry of the pores. Our calculations on the variation of T_{NI} with pore diameter agree with experimental data. Also, the calculated values of specific heat peak decrease with decrease in pore radius, in agreement with experimental trends.

Keywords

EN

61.30.-v   61.30.Cz   64.70.M-   61.30.Pq  

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2016
• Volume: 130
• Issue: 3
• Pages: 748-750

Dates

published

2016-09

received

2015-12-21

(unknown)

2016-06-10

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Identifiers

DOI

10.12693/APhysPolA.130.748