Additional absorptions found when sulfur hexafluoride and other electron scavenging species are dissolved in tetrakis (dimethylamino) ethylene (TMAE) are ascribed to charge‐transfer bands, and the order of the absorption onsets is related to the order of electron affinities. Sulfur hexafluoride is a weak acceptor, which by comparison with previous measurements appears to have a small positive value for Eav of about 0.60 eV. Some fluorocarbons, oxygen, and naphthalene are compared. Just as the perfluorocycloalkanes are more effective electron scavengers than the linear, they produce yellow solutions in TMAE, whereas the linear do not. All interactions are extremely weak. A marked enhancement of the absorption of TMAE in hexafluorobenzene as compared with hexafluorobenzene in TMAE is ascribed to a geometrical limit imposed on site saturation.

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