Matrix-isolation infrared spectrum and optimized structure of 2,3-dicyanonaphthalene in the T1 state

Photo-excited transient species of 2,3-dicyanonaphthalene produced during UV irradiation was studied by low-temperature matrix-isolation Fourier transform infrared (IR) spectroscopy. To identify the transient species, the density-functional-theory method was used for optimization of the geometrical structures and for estimation of the IR spectral patterns of the T1 and T2 states. By a comparison of the observed IR spectrum with the predicted spectral patterns, the observed photo-excited transient species was identified as the T1 state of 2,3-dicyanonaphthalene.