Emission spectra of alpha,omega-diphenyltetradecaheptaene (DP7) have been measured in polycrystalline n-tetradecane at 77 K. It is shown that DP7 exhibits the dual fluorescence from the 2(1)Ag (S-1) and 1(1)Bu (S-2) states not only in room temperature solution but also in a rigid matrix at 77 K. The measured fluorescence spectrum at 77 K was compared with the spectrum simulated with sum of Gaussians. The measured and calculated spectra agreed reasonably to each other. and the energy for the 2(1)Ag (S-1) to 1(1)Ag (S-0) fluorescence origin band was determined to be 16 660 +/- 40 cm(-1) in n-tetradecane at 77 K. (C) 2003 Elsevier B.V. All rights reserved.