Electronic and Vibrational States of Tetracene (Naphthacene)

Abstract

The absorption and fluorescence spectra of tetracene have been studied in substitutional solid solutions in naphthalene and in anthracene at 20°K. In agreement with theoretical predictions, the lowest excited singlet state at 20 246 cm^—1 is ¹B_2u, ¹L_a, since the transition with the ground state is polarized along the short molecular axis. Vibrational frequencies of tetracene are compared in ground and excited electronic states, and are compared with the vibrations of anthracene and naphthalene.