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Updated: Apr 23, 2026
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Halogen vs hydrogen bonding in thiazoline-2-thione stabilization with σ- and π-electron acceptors adducts:
Hamdy S El-Sheshtawy1, Hassan M A Salman2, Maged El-Kemary3
1Biotechnology and Fish Processing Department, Faculty of Aquatic and Fisheries Sciences, Kafrelsheikh University, 33516 Kafr ElSheikh, Egypt; Nanochemistry Laboratory, Chemistry Department, Faculty of Science, Kafrelsheikh University, 33516 Kafr ElSheikh, Egypt.
Abstract:
Molecular charge-transfer complexes (CT) between thiazoline-2-thione (THZ) and different σ- (I2) and π-acceptors (Tetracyanoethylene (TCNE), 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), and 2,3,5,6-tetrachloro-1,4-benzoquinone (CHL)) were investigated. UV-Vis absorption spectroscopy and theoretical calculations using both MP2/aug-cc-pVDZ-PP and B3LYP/6-311++G(d,p) level of theory were corroborated to study the nature of the stabilizing forces for THZ-I2, THZ-DDQ, THZ-TCNE, and THZ-CHL. Halogen bonding (XB) was the stabilizing attractive force in THZ-I2 and THZ-CHL whereas; hydrogen bonding (HB) was dominated in both THZ-TCNE, and THZ-DDQ complexes. Formation constant (K), extinction coefficient (ɛ), thermodynamic parameters such as enthalpy change (ΔH), entropy (ΔS), and Gibbs free energy (ΔG) were measured in different solvents.
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