Electron Affinities of the Heavy Elements

Horizontal analysis has been employed to obtain quantitative estimates for the electron affinities of the elements of the three long periods of the Mendeleev periodic table. Values for the A subgroup were normalized to published experimental values for bromine and iodine and an estimate for astatine, while those for the B subgroup were based on experimental values for the alkali and noble metals. The results are consistent with most of the published experimental values and with those negative ions detected. The near agreement between the electron affinities of the alkali metals and those of the excited rare gases with similar outer-shell configurations suggests that most of the polarization contribution arises from the outer shell.