Comparative Density Functional Theory Approaches for Investigating the Electro-Optical Properties of 5CB Liquid Crystal Molecules

[1]    Kumar, N., Singh, P., Upadhyay, P., Chaudhary, S., et al., 2020. Odd–even effect of 7O. m liquid crystal compound series studied under the effect of the electric field by density functional theory (DFT) methods. The European Physical Journal Plus, 135, p.388.

[2]    Simpson, S.H., Richardson, R.M., and Hanna, S., 2005. Calculation of the birefringence’s of nematic liquid crystals at optical and infrared wavelengths. The Journal of Chemical Physics, 123(13), p.134904. 

[3]    Omar, A.Z., Alazmi, M.L., Alsubaie, M.S., Hamed, E.A., Ahmed, H.A. and El-Atawy, M.A., 2023. Synthesis of New Liquid-Crystalline Compounds Based on Terminal Benzyloxy Group: Characterization, DFT and Mesomorphic Properties. Molecules, 28(9), p.3804.

[4]    Kumar, N., Singh, P., Thapa, K.B. and Kumar D., 2020. Molecular spectroscopy and adverse optical properties of N-(p-hexyloxy-benzylidene)–ptoluidine (HBT) liquid crystal molecule studied by DFT methodology. IOPSciNotes 1, p.015202.

[5]    Sundaram, S., Vijayakumar, V., and Balasubramanian, V., 2022. Electronic and structure conformational analysis (HOMO-LUMO, MEP, NBO, ELF, LOL, AIM) of hydrogen bond binary liquid crystal mixture: DFT/TD-DFT approach. Computational and Theoretical Chemistry, 1217, p.113920.

[6]    Sundaram, S., Vijayakumar, V., Balasubramanian, V., Chitravel, T., and Sukanya, R., 2023. Experimental and theoretical (DFT) approaches on novel ternary liquid crystals derived from asymmetric aromatic dicarboxylic acid. Journal of Molecular Liquids, 390, p.123193.

[7]    Vecchi, I., Arcioni, A., Bacchiocchi, C., Tiberio, G., Zannoni, C. and Zanirato, P., 2007. A Non-Standard Temperature Dependence of the Order Parameter of the 5CB Liquid Crystal Doped with an Azo-Derivative. Molecular Crystals and Liquid Crystals, 465(1), pp.271–281. 

[8]    El-Demerdash, S.H., Halim, S.A., El-Nahas, A.M. et al. 2023. A density functional theory study of the molecular structure, reactivity, and spectroscopic properties of 2-(2-mercaptophenyl)-1-azaazulene tautomers and rotamers. Scientific Reports, 13, p.15626.

[9]    Borioni, J.L., Puiatti, M., Vera, D.M.A., and Pierini, A.B., 2017. In search of the best DFT functional for dealing with organic anionic species. Physical Chemistry Chemical Physics, 19(13), pp.9189–9198. 

[10]  Kushwaha, Y., and Yadava, U., 2025. DFT investigation on the effect of asymmetry on electro-optical properties of bent-core liquid crystals. Phase Transitions, 98(1), pp.55–71.

[11]  Apra, E., Bylaska, E.J., W. A., de Jong, N. Govind, et. al, 2020. NWChem: Past, present, and future. The Journal of Chemical Physics, 152, p.184102.

[12]  Becke, A., 1993. Density-functional thermochemistry. III. The role of exact exchange.  Journal of Chemical Physics, 98, p.5648.

[13]  Lee, C., Yang, W., and Parr, R.G., 1988. Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density. Physical Review B, 37, p.785.

[14]  Ahmed, H.A., Hagar, M., Alhaddad, O.A. and Zaki, A.A., 2020. Optical and Geometrical Characterizations of Non-Linear Supramolecular Liquid Crystal Complexes. Crystals, 10(8), p.701.

[15]  Hay, P.J., and Wadt, W.R., 1985.  Ab initio effective core potentials for molecular calculations. Potentials for the transition metal atoms Sc to Hg. The Journal of Chemical Physics, 82, pp.270-283.

[16]  Gwizdała, W., Górny, K., and Gburski, Z., 2011. The dynamics of 4-cyano-4-n-pentylbiphenyl (5CB) mesogen molecules located between graphene layers MD study. Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 79(4), pp.701–704. 

[17]  Pan, P., Tsai, R., Chen, Y. and Pan, L., 2003. Optical Constants of Two Typical Liquid Crystals 5CB and PCH5 in the THz Frequency Range. Journal of Biological Physics, 29(2-3), pp.335-338.

[18]  Mishra, M., Kumar, M., Singh, D., Thapa, K.B., Pandey, G., and Kumar, D., 2024. DFT study of difluoro & trifluoro bi-cyclohexane based dimer for application in electronic and optical devices. Journal of Molecular Liquids, 414, p.126109.

[19]  Pandey, A.K, Pandey, K.K, Dubey, D.D., Singh, V. and Dwivedi, A., 2025. Study of electro-optical behavior of nematic liquid crystal p- butoxybenzylidene, p-heptylaniline (BBHA) under applied electric field by using density functional theory. Journal of Molecular Liquids, 420, p.126839.

[20]  Kobinata, S., Nakajima, Y., Yoshida, H., and Maeda, S., 1981. The Order Parameters of Some Nematic Liquid Crystals Measured by the Resonance Raman Effect and Its Relevance to the Nematic-Isotropic Phase Transition. Molecular Crystals and Liquid Crystals, 66(1), pp.67–74. 

[21]  Domagała, M., Jabłoński, M., Dubis, A. T., Zabel, M., Pfitzner, A. and Palusiak, M., 2021. Testing of Exchange-Correlation Functional of DFT for a Reliable Description of the Electron Density Distribution in Organic Molecules. International Journal of Molecular Sciences, 23(23), p.14719.

[22]  Bursch, M., Mewes, M., Hansen, A. and Grimme, S., 2022. Best-Practice DFT Protocols for Basic Molecular Computational Chemistry. Angewandte Chemie, 134(42), p.e202205735.

[23]  Singh, P., Thapa, K. B., Kumar, N. and Kumar, D., 2019. Omnidirectional Reflection Band of One-dimensional Periodic Structure (1DPS) of Si/SiO2 with Defect Mode of Nematic Liquid Crystal (5CB). Journal of Physical Science, 30(3), pp.117–129.

[24]  Garg, K, Chakraborty, A, Bhattacharjee, A, Choudhury, S P, Kumari, S, and Bhattacharjee, D. 2024. A DFT analysis of thermodynamical, structural and non-linear optical properties of liquid crystalline compounds (5O.m, m = 14, 16). Journal of Molecular Liquids, 414, p.126124.

[25]  Garg, K., Chakraborty, A., Żak, M., Herman, J., Naha, A., and Bhattacharjee, D., 2025. Impact of fluorine substitution on benzene ring in two fluorinated liquid crystal compounds: a comprehensive analysis using TG-DTA, FT-IR, UV, and PED techniques. Discover Applied Sciences, 7, p.471.

[26]  Orlova, T., Piven A., Darmoroz, D., Aliev, T., Razik T.M.T.A., Boitsev, A., Grafeeva, N., and Skorb E., 2023. Machine learning for soft and liquid molecular materials, Digital Discovery, 2, pp.298-315.

[27]  Włodarska, M., 2020. DFT Studies of Selected Epoxies with Mesogenic Units–Impact of Molecular Structure on Electro-Optical Response. International Journal of Molecular Sciences, 22(7), p.3424.

[28]  Vecchi, I., Arcioni, A., Bacchiocchi, C., Tiberio, G., Zanirato, P., and Zannoni, C., 2007. Expected and unexpected behavior of the orientational order and dynamics induced by azobenzene solutes in a nematic. The Journal of Physical Chemistry B, 111(13), pp.3355-62.

[29]  Pessa, A.A., Zola, R.S., Perc, M. and Ribeiro, H.V., 2021. Determining liquid crystal properties with ordinal networks and machine learning. Chaos, Solitons & Fractals, 154, p.111607.

[30]  Pan, R.P., Hsieh, C.F., Pan, C.L. and Chen, C.Y., 2008. Temperature-dependent optical constants and birefringence of nematic liquid crystal 5CB in the terahertz frequency range. Journal of Applied Physics. 1., 103(9), p.093523. 

[31]  Shukla A., Prasad R., and Kumar P., 2021. 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, pp.18-28.

[32]  Chen, Z., Jiang, L., and Ma, H. 2016. Calculation on frequency and temperature properties of birefringence of nematic liquid crystal 5CB in terahertz band. Chemical Physics Letters, 645, pp.205-209.