Fluorescence spectrum of phenanthrene single crystal at 4°K

Abstract

The fluorescence spectrum of anthracene-free phenanthrene single crystals at 4ºK has been investigated. The whole spectrum has been analysed in terms of three superimposed spectra, one (weak) originating in a free pure exciton level of the pure phenanthrene crystal and two associated with defects. One of the defect spectra is very strong. All three series can be analysed in terms of similar if not identical vibrational frequencies.