Next Article in Journal
Synthesis of Ag Loaded ZnO/BiOCl with High Photocatalytic Performance for the Removal of Antibiotic Pollutants
Next Article in Special Issue
Molecular Dynamics and Kinetics of Isothermal Cold Crystallization in the Chiral Smectogenic 3F7HPhH6 Glassformer
Previous Article in Journal
RF-Characterization of HZO Thin Film Varactors
Article

Mesomorphic Behaviour and DFT Insight of Arylidene Schiff Base Liquid Crystals and Their Pyridine Impact Investigation

1
Department of Chemistry, Faculty of Science, Alexandria University, Alexandria 21321, Egypt
2
Department of Chemistry, Faculty of Science, the Maharaja Sayajirao University of Baroda, Vadodara 390002, Gujarat, India
3
Biological and Environmental Sciences & Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
4
Department of Chemistry, College of Sciences, Taibah University, Yanbu 46423, Saudi Arabia
5
Department of Chemistry, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
*
Author to whom correspondence should be addressed.
Academic Editor: Antonio Martins Figueiredo Neto
Crystals 2021, 11(8), 978; https://doi.org/10.3390/cryst11080978
Received: 9 July 2021 / Revised: 7 August 2021 / Accepted: 14 August 2021 / Published: 18 August 2021
(This article belongs to the Special Issue Smectic Liquid Crystals)
A new series of Schiff base liquid crystal have been prepared and studied. Schiff bases of p-alkyl aniline derivatives and 4-phenyl pyridine-4′-carbaldehyde were prepared. The terminal alkyl groups substituting aniline are of varied chain length, namely C8, C12 and C14. The structures of the compounds were elucidated by 1H NMR and 13C NMR. The mesomorphic thermal and optical characteristics of the samples were determined via differential thermal analysis (DSC) and polarization optical microscopy (POM). All compounds exhibit enantiotropic dimorphic mesophase behaviour, referred to as smectic X1 (SmX1) and smectic X2 (Sm A). Experimental results obtained for the mesophases were correlated with density functional theory (DFT) theoretical calculations. The results of the new series are further compared to two series of compounds bearing pyridine (two ring Schiff bases) and biphenyl, respectively, in their mesogens. The series of compounds of one pyridine ring are generally not mesomorphic. The results indicate that the alkyl chain length has a strong impact on the mesomorphic characteristics and thermal stabilities of the different mesophases. As a trend, the temperature ranges of both of smectic mesophases of all compounds are higher in new compounds bearing the 4-phenyl pyridine moiety. In addition, the total mesophase range is generally higher in the new compounds when compared to their biphenyl analogues. Finally, theoretical DFT calculations were performed to illustrate the experimental finding of the mesomorphic behaviour in terms of the molecular geometry and aromaticity, π–π stacking and LOL-π. View Full-Text
Keywords: liquid crystal; schiff base; biphenyl; 4-phenyl pyridine; DFT liquid crystal; schiff base; biphenyl; 4-phenyl pyridine; DFT
Show Figures

Figure 1

MDPI and ACS Style

Zakaria, M.A.; Alazmi, M.; Katariya, K.D.; El Kilany, Y.; El Ashry, E.S.H.; Jaremko, M.; Hagar, M.; Mohammady, S.Z. Mesomorphic Behaviour and DFT Insight of Arylidene Schiff Base Liquid Crystals and Their Pyridine Impact Investigation. Crystals 2021, 11, 978. https://doi.org/10.3390/cryst11080978

AMA Style

Zakaria MA, Alazmi M, Katariya KD, El Kilany Y, El Ashry ESH, Jaremko M, Hagar M, Mohammady SZ. Mesomorphic Behaviour and DFT Insight of Arylidene Schiff Base Liquid Crystals and Their Pyridine Impact Investigation. Crystals. 2021; 11(8):978. https://doi.org/10.3390/cryst11080978

Chicago/Turabian Style

Zakaria, Mohamed A., Mohammed Alazmi, Kanubhai D. Katariya, Yeldez El Kilany, El S.H. El Ashry, Mariusz Jaremko, Mohamed Hagar, and Sayed Z. Mohammady. 2021. "Mesomorphic Behaviour and DFT Insight of Arylidene Schiff Base Liquid Crystals and Their Pyridine Impact Investigation" Crystals 11, no. 8: 978. https://doi.org/10.3390/cryst11080978

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop