Electron-transfer reactions between ions and
molecules in solution have been the subject of
considerable experimental study during the past
three decades. Experimental results have also been
obtained on related phenomena, such as reactions
between ions or molecules and electrodes, charge-transfer
spectra, photoelectric emission spectra of
ionic solutions, chemiluminescent electron transfers,
electron transfer through frozen media, and
electron transfer through thin hydrocarbon-like
films on electrodes.