Iranian Journal of Mathematical Chemistry

Iranian Journal of Mathematical Chemistry

Odd-Even Effect Observed in the Electro-Optical Properties of the Homologous Series of HnCBP Liquid Crystal Studied under the Impact of the Electric Field: A Theoretical Approach

Document Type : Research Paper

Authors
Narinder Kumar 1
Pawan Singh 1
Khem Thapa 1
Devesh Kumar 2
1 Department of Physics, School of Physical & Decision Sciences, Babasaheb Bhimrao Ambedkar University, Vidya Vihar, Raebareli Road, Lucknow (U.P.) 226025 INDIA
2 Department of Physics, School of Physical & Decision Sciences, Babasaheb Bhimrao Ambedkar University, Vidya Vihar, Raebareli Road, Lucknow (U.P.) 226025 INDIA Email:dkclcre@yahoo.com
10.22052/ijmc.2020.232036.1503
Abstract
The liquid crystal (LC) 4-4′-disubstituted biphenyls (HnCBP) of the general line formula HO-(CnH2n+1)-O-C6H4-C6H4-CN (n=1-12) shows the odd-even effect under the applied electric field. The odd-even effects are observed in the HOMO-LUMO gap, birefringence, order parameter, and dipole moment. The odd carbon atom number of alkyl chain shows HOMO-LUMO gap, birefringence and order parameter in the upward direction and even carbon atom number of alkyl chain shows in the downward direction; however the dipole moment exhibits a shift of even carbon number of alkyl chain in the upward direction and odd carbon number of alkyl chain in the downward direction.
Keywords
Liquid crystals (HnCBP)
Electric field
Odd-Even effect
DFT (B3LYP). Molecular Spectroscopy

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Iranian Journal of Mathematical Chemistry
Volume 11, Issue 4
Autumn 2020
Pages 239-254