Investigation of Physical, Opto-Electronics and Insulating Properties of PPPCC Liquid Crystal Molecule by Density Functional Theory (DFT) Method: A Theoretical Approach
Abstract
In this paper, we have studied the physical, electro-optical and thermal properties of PPPCC liquid crystal molecule. Density functional theory (DFT) with the B3LYP functional and the 6-31G(d,p) basis set is employed for the optimization and analysis of the p-Propoxyphenyl trans-4-pentylcyclohexanecarboxylate (PPPCC) LC molecule. Various physical properties, such as HOMO-LUMO energy levels, electro-optical properties, and global parameters, are computed and analysed for the PPPCC liquid crystal. We have reported the birefringence of p-Propoxyphenyl trans-4-pentylcyclohexanecarboxylate (PPPCC) liquid crystal under the effect of an external electric field. The UV-Visible analysis leaves a strong peak at 252 nm due to π-π* transitions. HOMO-LUMO band gap found to be 5.1 eV. The maximum stretching was observed at 1000 cm-1 due to the C-O stretching caused by the Ether in the PPPCC liquid crystal. The C-C stretching around 1600 cm-1 is found due to phenyl group present in PPPCC. The temperature-sensitive birefringence value of PPPCC makes it a suitable choice for modern optical technology applications. The refractive index remains unchanged at large applied electric fields, making it a suitable choice for opto-electronic devices in THz applications. Due to the large band gap, this molecule could be a suitable choice for insulating applications.
Downloads
References
G.W. Gray, Molecular Structure and the Properties of Liquid Crystals, (Academic Press, New York, London, 1962).
S. Chandrasekhar, Liquid Crystals, 2nd ed., (Cambridge University Press, Cambridge, 1992); W.R. Krigbaum, Y. Chatani, P.G. Barber, “The crystal structure of p-azoxyanisole,” Acta Cryst. B26, 97 (1970). https://doi.org/10.1107/s0567740870002005
A. Shukla, R.P. Tiwari, and P.K. Singh, “DFT-Based Study of Physical, Chemical and Electronic Behavior of Liquid Crystals of Azoxybenzene Group: p-azoxyanisole, p-azoxyphenetole, ethyl-p-azoxybenzoate, ethyl-p-azoxycinnamate and n-octyl-p-azoxycinnamate,” Online Journal of Chemistry, 1(1), 18–28 (2021). https://doi.org/10.31586/ojc.2021.010103
A.V. Zakharov, and L.V. Mirantsev, “Dynamic and dielectric properties of liquid crystals,” Phys. Solid. State. 45, 183–188 (2003). https://doi.org/10.1134/1.1537433/METRICS
M. Govindarajan, M. Karabacak, S. Periandy, and S. Xavier, “Vibrational spectroscopic studies, NLO, HOMO-LUMO and electronic structure calculations of α, α, α trichlorotoluene using HF and DFT,” Spectrochim Acta - Part A: Mol. Biomol. Spectrosc. 94, 53–64 (2012). https://doi.org/10.1016/j.saa.2012.03.074
D. Pegu, J. Deb, C. Van Alsenoy, and U. Sarkar, “Theoretical investigation of electronic, vibrational, and nonlinear optical properties of 4-fluoro-4-hydroxybenzophenone,” Spectrosc. Lett. 50, 232–243 (2017). https://doi.org/10.1080/00387010.2017.1308381
L. Sinha, O. Prasad, V. Narayan, S.R. Shukla, Raman, “FT-IR spectroscopic analysis and first-order hyperpolarisability of 3 benzoyl-5-chlorouracil by first principles,” Mol. Simul. 37, 153–163 (2011). https://doi.org/10.1080/08927022.2010.533273.
I. Haller, “Thermodynamic and static properties of liquid crystals,” Prog. Solid State Chem. 10, 103–118 (1975). https://doi.org/10.1016/0079-6786(75)90008-4
P. Upadhyay, M.K. Rastogi, and D. Kumar, “Polarizability study of nematic liquid crystal 4-cyano-4′-pentylbiphenyl (5CB) and its nitrogen derivatives,” Chem. Phys. 456, 41–46 (2015). https://doi.org/10.1016/j.chemphys.2015.03.011
D. de Sarkar, R. Deb, N. Chakraborty, G. Mohiuddin, R.K. Nath, and V.S.R. Nandiraju, “Cholesterol-based dimeric liquid crystals: Synthesis, mesomorphic behaviour of frustrated phases and DFT study,” Liq. Cryst. 40, 468–481 (2013). https://doi.org/10.1080/02678292.2012.757814
D. Bhattacharjee, T.K. Devi, R. Dabrowski, A. Bhattacharjee, Birefringence, polarizability order parameters and DFT calculations in the nematic phase of two bentcore liquid crystals and their correlation, J Mol Liq 272 (2018) 239–252. https://doi.org/10.1016/j.molliq.2018.09.052.
D. Bhattacharjee, T.K. Devi, R. Dabrowski, and A. Bhattacharjee, “Birefringence, polarizability order parameters and DFT calculations in the nematic phase of two bentcore liquid crystals and their correlation,” J. Mol. Liq. 272, 239–252 (2018). https://doi.org/10.1016/J.MOLLIQ.2018.09.052
V.G.K.M. Pisipati, and S.B. Rananavare, “Interdigitated smectic a and b mesophases in higher homologues of the 50.m series,” Liq. Cryst. 13, 757–764 (1993). https://doi.org/10.1080/02678299308027291
M. Govindarajan, S. Periandy, and K. Carthigayen, “FT-IR and FT-Raman spectra, thermo dynamical behavior, HOMO and LUMO, UV, NLO properties, computed frequency estimation analysis and electronic structure calculations on α-bromotoluene,” Spectrochim. Acta - Part A: Mol. Biomol. Spectrosc. 97, 411–422 (2012). https://doi.org/10.1016/j.saa.2012.06.028
D. Bhattacharjee, R. Dabrowski, and A. Bhattacharjee, “Theoretical investigation of nonlinear optical and vibrational properties of two liquid crystalline compounds,” J. Mol. Liq. 255, 80–92 (2018). https://doi.org/10.1016/J.MOLLIQ.2018.01.157
H. Wang, M.Y. Jin, R.C. Jarnagin, T.J. Bunning, W. Adams, B. Cull, Y. Shi, et al., “Thermally stable nonlinear optical activity in a smectic-A liquid crystal,” Nature, 384, 244–247 (1996). https://doi.org/10.1038/384244a0
D. Gupta, and A. Bhattacharjee, “Detailed investigation of N-(4-n-pentyl-oxybenzylidene)- 4′-n-hexylaniline liquid crystal molecule,” J. Mol. Struct. 1196, 66–77 (2019). https://doi.org/10.1016/j.molstruc.2019.06.068
E. Apra, E.J. Bylaska, W.A. de Jong, N. Govind, et. al. “NWChem: Past, present, and future”, The Journal of Chemical Physics, 152, 184102 (2020). http://dx.doi.org/10.1063/5.0004997
Y. Kumar, and N. Kumar, “Electro-optical Effect of 4-n-alkyl-sulfanyl-4' isothiocyanate-biphenyl Liquid Crystal Homologous Series Under Terahertz Frequency: A Theoretical Approach,” Makara Journal of Science, 27(4), Article 1, (2023). https://doi.org/10.7454/mss.v27i4.1497
N. Kumar, P. Singh, K.B. Thapa, and D. Kumar, “Molecular spectroscopy and adverse optical properties of N-(p-hexyloxy-benzylidene)–ptoluidine(HBT) liquid crystal molecule studied by DFT methodology, IOPSciNotes, 1, 015202 (2020). https://doi.org/10.1088/2633-1357/ab7f83
T. Orlova, A. Piven, D. Darmoroz, T. Aliev, T.M.T.A. Razik, A. Boitsev, et al., “Machine learning for soft and liquid molecular materials,” Digital Discovery, 2, 298-315 (2023). https://doi.org/10.1039/D2DD00132B
Copyright (c) 2026 Tikaram, Yogesh Kumar, Narinder Kumar

This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgment of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgment of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).



