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Are there examples of UV-Vis emission from charge-separated states? The cases I have encountered have only absorption. Is the recombination process of a nonradiative kind by necessity?

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There are at least cases in which charge recombination results in an excited species that deactivates via fluorescence.

Imagine the ionization of a hydrocarbon ($\ce{RH}$) to yield a radical cation and a solvated electron. \[\ce{RH ->[\mathrm{e-beam}] RH^{+\cdot} + e-}\]

Trap the electron by reducing an aromatic hydrocarbon ($\ce{ArH}$) to the coresponding radical anion.

\[ \ce{ArH +e- -> ArH^{-\cdot}}\]

Charge recombination between the radical cation and the radical anion can yield $\ce{ArH}$ in an excited state.

\[\ce{RH^{+\cdot} + ArH^{-\cdot} -> RH + ArH^{\ast}} \]

Back in the days, Alexander D. Trifunac did a lot of work on that at ANL.

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