Free electrons, the simplest radicals of them all: Chemistry of aqueous electrons as studied by mass spectrometry

In the present manuscript we review the chemistry of aqueous electrons, as studied by Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. FT-ICR studies of the (H ₂O) _n ^- reactions have the advantage that compared with bulk solutions the electrons exhibit long lifetimes, and impurity effects can be completely eliminated. The review demonstrates that aqueous electrons, the simplest chemical reagents, exhibit a multifaceted chemistry, and may provide new insights into the aqueous chemistry of neutral and anionic radicals. We show that the cluster reactions can be loosely classified into several categories, and give representative examples for each of them.