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We have experimentally studied the ultrafast relaxation dynamics of aromatic cation radicals following photoionization. In polar solvents, the absorption due to the naphthalene cation radical first decreases in the subpicosecond range, then increases in tens of picoseconds. From measurements of excitation power, solvent, and sample dependencies, it has been considered that the first decrease is due to the geminate recombination and the slower increase is to the solvent dynamics of the reorganization