title: Molecular interactions in 1-ethyl-3-methylimidazolium acetate ion pair: a density functional study.
abstract: The density functional method is used to obtain the molecular structure, electron density topography, and vibrational frequencies of the ion pair 1-ethyl-3-methylimidazolium acetate. Different conformers are simulated on the basis of molecular interactions between the 1-ethyl-3-methylimidazolium cation and acetate anion. The lowest energy conformers exhibit strong C-H...O interionic interactions compared with other conformers. Characteristic vibrational frequencies of the ion pair and their shifts with respect to free ions are analyzed via the natural bond orbitals and difference electron density maps coupled with molecular electron density topology. Theoretically scaled vibrational frequencies are also compared with the spontaneous Raman scattering and attenuated total reflection infrared absorption measurements.
authors.affiliation: Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: Nilesh R
authors.initials: NR
authors.lastname: Dhumal
authors.forename: Hyung J
authors.initials: HJ
authors.lastname: Kim
authors.forename: Johannes
authors.initials: J
authors.lastname: Kiefer
mesh_terms: D003198:Computer Simulation; D006860:Hydrogen Bonding; D007093:Imidazoles / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D008956:Models, Chemical; D015394:Molecular Structure; D014732:Vibration
chemical_list: D007093:Imidazoles; D007477:Ions; C518739:1-ethyl-3-methylimidazolium