  While ionization of some polyatomic molecular liquids (such as water and
aliphatic alcohols) yields so-called "solvated electrons" in which the excess
electron density is localized in the interstices between the solvent molecules,
most organic and inorganic liquids yield radical anions and cations in which
the electron and spin densities reside on the solvent molecule or, more
commonly, a group of such molecules. The resulting multimer ions have many
unusual properties, such as high rates of diffusive hopping. The "solvated
electron" can be regarded as a variant of a multimer radical anion in which the
charge, while perturbing the solvent molecules, mainly resides in the space
between these molecules. We give several examples of less known modes for
electron localization in liquids that yield multimer radical anions (such as
C6F6, benzene, acetonitrile, carbon disulfide and dioxide, etc.) and holes
localization in liquids that yield multimer radical cations (such as
cycloalkanes). Current understanding of the reaction properties for these
high-mobility solvent radical anions and cations is discussed.

Chemical Physics