Phase Behaviour Study of a Mesogen in a Solvent Role of Molecular Rigidity and Configurational Entropy

Open Access

Year : 2023 | Volume :10 | Issue : 1 | Page : 1-9
By

    P. Lakshmi Praveen

  1. Assistant Professor, Department of Physics, Veer Surendra Sai University of Technology, Burla, Sambalpur, Odisha, India

Abstract

The phase behaviour of a nematogen 4’-n-pentyloxy-4-biphenylcarbonitrile (POBPCB) has been studied with respect to the translational and orientational motions. The charges of atoms and their dipole moments have been estimated by implementing the complete neglect differential overlap (CNDO/2) method. The long-range interactions have been analyzed using modified Rayleigh- Schrodinger Perturbation theory together with the multicentred-multipole expansion scheme. The “6- exp” potential function has been considered to study the short-range interactions. The minimum energy configurations obtained during the different modes of interactions have been taken as input to calculate the configurational probability using the Maxwell-Boltzmann in polar aprotic solvent i.e., Dimethylformamide (DMF) at room temperature (300 K) and nematic-isotropic transition temperature (340.5 K). A comparison between rigidity analysis and configurational entropy explains the nematic behaviour of the compound.

Keywords: 4’-n-pentyloxy-4-biphenylcarbonitrile (POBPCB), molecular rigidity, configurational entropy, Dimethylformamide (DMF), Rayleigh-Schrodinger Perturbation theory

[This article belongs to Research & Reviews : Journal of Physics(rrjophy)]

How to cite this article: P. Lakshmi Praveen Phase Behaviour Study of a Mesogen in a Solvent Role of Molecular Rigidity and Configurational Entropy rrjophy 2023; 10:1-9
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Regular Issue Open Access Article
Volume 10
Issue 1
Received November 8, 2020
Accepted August 12, 2020
Published January 8, 2023