Absence of dual fluorescence in jet-cooled benzonitrile and p-tolunitrile

The observation of a dual fluorescence in the emission spectra of jet-cooled benzonitrile and p-tolunitrile has been reported by Mordzinski et al. [J. Phys. Chem. A 101 (1997) 8221], and a broad, red-shifted component has been assigned as a transition from a rehybridized intramolecular charge-transfer (RICT) state. However, the dispersed fluorescence spectra measured at much higher resolution clearly show that the broad feature consists of many sharp features, indicating that emission from the RICT state is absent.