Super-alkali atom

The first experiments were carried out on films of solid CeO) 100 to 1000 A thick, exposed to alkali metal vapors.[Ha91a ] It was observed that the conductivity increased by more than seven orders of magnitude, to 500 (fl cm) . This is still a much lower conductivity than any metallic element, but on the order of such organic systems as doped polyacetylene. Haddon et al. made the plausible suggestion, subsequently proved, that the smaller alkali ions were intercalated into the voids between the much larger fullerenes, and donated their charge to the unoccupied fullerene molecular orbital. The ratio of alkali atoms to fuUerenes in the (super) conducting phase was not then known, nor was it known whether the structure was based on the... 

The electronically excited rare gas atom is sometimes called a super-alkali because its ionization potential is so low. There are also super-halogens and not only super-alkalis (Herschbach, 1966 Bersohn, 1976). The super-halogen has a particularly high electronic affinity NO2, with an electron affinity of about 2.4 eV, is an example so is (CN)2. Excited states of organic molecules are used as effective electron donors. Complexes of transition metals in unusually high oxidation states are keen acceptors and vice versa for complexes where the metal is nominally neutral. 

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