[en] Pulse radiolysis of alkali metal cations in isopropylamine indicates the formation of three distinct optical bands attributed to solvated electrons, esup(-)sub(s), ion-pairs (M⁺,esup(-)sub(s)) and alkali anions M^-. It is found that the ion-pair spectra exhibit a distinct blue shift from that of esup(-)sub(s). Comparisons with results obtained in ethylamine, tetrahydrofuran and other solvents demonstrate that the position of the ion-pair band can be correlated with the percent atomic character observed by ESR for the 'monomer' species in alkali metal solutions. Results are presented for the alkali metal series, Li, Na, K, Rb and Cs. (Auth.)