Cluster Formation through Hydrogen Bond Bridges across Chloride Anions in a Hydroxyl‐Functionalized Ionic Liquid. Issue 7 (19th March 2019)

• Record Type: Journal Article
• Authors: Panja, Sumit Kumar; Haddad, Boumediene; Debdab, Mansour; Kiefer, Johannes; Chaker, Yassine; Bresson, Serge; Paolone, Annalisa
• Is Part Of: Chemphyschem. Volume 20:Issue 7(2019)
• Page Start: 936
• Page End: 940
• Publication Date: 2019-03-19
• Subjects: cluster formation -- density functional calculations -- H-bonding interactions -- ionic liquids -- ion pairs; Chemistry, Physical and theoretical -- Periodicals; 541.05
• DOI: 10.1002/cphc.201801206
• Languages: English
• ISSNs: 1439-4235

Abstract

Abstract: Several recent studies of hydroxyl‐functionalized ionic liquids (ILs) have shown that cation‐cation interactions can be dominating these materials at the molecular level when the anion involved is weakly interacting. The hydrogen bonds between the like ions led to the formation of interesting chain‐like, ring‐like, or distinct dimeric (i. e. two ion pairs) supermolecular clusters. In the present work, vibrational spectroscopy (ATR‐IR and Raman) and density functional theory (DFT) calculations of the hydroxyl‐functionalized imidazolium ionic liquid C2 OHmimCl indicate that anion‐cation hydrogen bonding interactions are dominating, leading to the formation of distinct dimeric ion pair clusters. In this arrangement, the Cl − anions function as a bridge between the cations by establishing bifurcated hydrogen bonds with the OH group of one cation and the C(2)‐H of another cation. Cation–cation interactions, on the other hand, do not play a significant role in the observed clusters. Abstract : Peculiar ion pairs : A combined theoretical and experimental study of a hydroxyl‐functionalized ionic liquid provides strong evidence for the formation of distinct ion‐pair dimers in the condensed‐phase material. The strongly‐interacting chloride anions act as a hydrogen bonding bridge between the cations, and cation‐cation interactions are negligible.