The electronic and topological properties of interactions between 1-butyl-3-methylimidazolium hexafluorophosphate/tetrafluoroborate and thiophene

Abstract

Density functional calculations have been performed to explore the interactions of thiophene and two ionic liquids of 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]⁺[PF₆]⁻) and 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]⁺[BF₄]⁻). The electronic properties and topological properties of [BMIM]⁺[PF₆]⁻-thiophene and [BMIM]⁺[BF₄]⁻-thiophene were analyzed. The calculated results reveal that the dominant interactions of C2--H2⋯F hydrogen bonds in [BMIM]⁺[PF₆]⁻ or [BMIM]⁺[BF₄]⁻ were not destroyed by the thiophene interactions with [BMIM]⁺[PF₆]⁻ and [BMIM]⁺[BF₄]⁻. The C--H ([BMIM]⁺⋯π (thiophene) hydrogen bonds and H(thiophene)⋯F([PF₆]⁻ or [BF₄]⁻ hydrogen bonds play crucial roles in the adsorption of thiophene on [BMIM]⁺[PF₆]⁻ and [BMIM]⁺[BF₄]⁻.