Multiple charge-transfer-induced local exciton levels in doped naphthalene crystals

Measurements of the absorption spectra of naphthalene crystals doped with benzene derivatives are reported. For a typical dopant, a set of bands (some genuinely local, some due to resonances) is observed. The patterns of local levels are interpreted in terms of the recently proposed two-dimensional cluster model. It gives a good qualitative description of the general features of the observed spectra. Probable reasons of quantitative discrepancies are discussed.