beta-carotene and 1-butyl-3-methylimidazolium-tetrafluoroborate

A detailed study was explored to compare the transient absorption spectra of the neat 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF(4)]) with its solution in water or acetonitrile. It was concluded that the excited triplet state (3)[bmim](+*) was produced after 266 nm laser irradiation, and then the neutral radical [bmim] and the cation radical [bmim] (2+) were formed through two possible paths. The transient absorption spectra of the neat [bmim][BF(4)] and its solution were similar but the reaction kinetics were different due to their different local structures such as dimeric or cluster. The energy transfer between excited [bmim][BF(4)] and β-carotene further affirmed the existence of (3)[bmim](+*). And the reaction that the hydrated electron captured by [bmim](+) to produce [bmim] in solution was observed.

Topics: Acetonitriles; beta Carotene; Borates; Dimerization; Electrons; Energy Transfer; Fluorides; Imidazoles; Ionic Liquids; Ions; Kinetics; Lasers; Photochemistry; Photolysis; Solutions; Spectrophotometry; Water