Interaction between ionic liquid cation and water: infrared predissociation study of [bmim]+·(H2O)n clusters. Issue 28 (29th June 2016)

• Record Type: Journal Article
• Authors: Voss, Jonathan M.; Marsh, Brett M.; Zhou, Jia; Garand, Etienne
• Is Part Of: Physical chemistry chemical physics. Volume 18:Issue 28(2016)
• Page Start: 18905
• Page End: 18913
• Publication Date: 2016-06-29
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c6cp02730j
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : The infrared predissociation spectra of [bmim] + ·(H2 O) n, n = 1–8, in the 2800–3800 cm −1 region are presented and analyzed with the help of electronic structure calculations. Abstract : The infrared predissociation spectra of [bmim] + ·(H2 O) n, n = 1–8, in the 2800–3800 cm −1 region are presented and analyzed with the help of electronic structure calculations. The results show that the water molecules solvate [bmim] + by predominately interacting with the imidazolium C2–H moiety for the small n = 1 and 2 clusters. This is characterized by a redshifted and relatively intense C2–H stretch. For n ≥ 4 clusters, hydrogen-bond interactions between the water molecules drive the formation of ring isomers which interact on top of the imidazolium ring without any direct interaction with the C2–H. The water arrangement in [bmim] + ·(H2 O) n is similar to the low energy isomers of neutral water clusters up to the n = 6 cluster. This is not the case for the n = 8 cluster, which has the imidazolium ring disrupting the otherwise preferred cubic water structure. The evolution of the solvation network around [bmim] + illustrates the competing [bmim] + –water and water–water interactions.