Spectrum and Reactivity of the Solvated Electron in the Ionic Liquid Methyltributylammonium Bis(trifluoromethylsulfonyl)imide

James F. Wishart and Pedatsur Neta

J. Phys. Chem. B 107, 7261-7267 (2003). [Find paper at ACS Publications] or use ACS Articles on Request

Abstract:

Fast pulse radiolysis transient absorption experiments were conducted on the ionic liquid methyltributylammonium bis(trifluoromethylsulfonyl)imide (R₄NNTf₂). The solvated electron was observed to have a very broad absorption band peaking at 1400 nm (e = 2.4 x 10⁴ L mol^-1 cm^-1) and a radiolytic yield (G) of 0.6 x 10^-7 mol J^-1. Dry electron capture by aromatic solutes, such as benzophenone and pyrene, is very efficient in R₄NNTf₂. Reactions of the solvated electron with the same compounds are diffusion limited, with rate constants of only k ~ (1 to 2) x 10⁸ L mol^-1 s^-1 due to the high viscosity of the ionic liquid.