Phosphorescence and Zeeman Spectra of Anthracene in a Mixed Crystal

Phosphorescence has been observed at 4.2°K for anthracene-h10 and anthracene-d10 dissolved in a phenazine host crystal. The sharp-line spectra permit a detailed analysis of the anthracene vibrational frequencies and the observation of the Zeeman splitting of the emitting triplet level. Analysis of the relative intensities among the Zeeman components of the electronic origin of emission in a 40.6 kG magnetic field shows that a long-axis spin state provides 95% of the radiative spin-state activity in the anthracene phosphorescence.