Premium
Influence of Hydration on the Structure and Interactions of Ethaline Deep‐Eutectic Solvent: A Spectroscopic and Computational Study
Author(s) -
Kalhor Payam,
Zheng YanZhen,
Ashraf Hamad,
Cao Bobo,
Yu ZhiWu
Publication year - 2020
Publication title -
chemphyschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/cphc.202000165
Subject(s) - ionic liquid , chemistry , hydrogen bond , choline chloride , aqueous solution , deep eutectic solvent , spectroscopy , molecule , eutectic system , ethylene glycol , ionic bonding , solvent , ion , crystallography , organic chemistry , microstructure , physics , quantum mechanics , catalysis
Deep‐eutectic solvents (DESs) are regarded as alternative green solvents to ionic liquids. In this work we report the structural properties and hydrogen bonding (H‐bonding) interactions of an aqueous DES system. The used DES, ethaline (ETH), is composed of choline chloride and ethylene glycol (EG) in 1 : 2 molar ratio. The investigations were carried out by FTIR spectroscopy combined with quantum chemical calculations. Excess spectroscopy and two‐dimensional correlation spectroscopy (2D‐COS) were used to explore the data in detail. The results showed that, upon mixing, ETH transforms to EG dimers and trimers and D 2 O clusters transform to various ETH‐D 2 O complexes. Theoretical calculations show that water molecules insert between the anion and cation of ETH, break the strong doubly ionic Cl − … H−O Ch+ H‐bond, share charges of the ions and form H‐bond with them, thus modulate the interaction properties of ETH. This study deepens our molecular‐level understanding of the system and would shed light on its applications.