High-resolution absorption and fluorescence of the 1-hydrobinaphthyl radical in the irradiated naphthalene crystal

The strong absorption band at 710 nm in an irradiated naphthalene crystal was studied at 4.2 K. Evidence from the deuterium shift, the absorption spectrum in a 50:50 C10H8-C10D8 crystal, and the fluorescence spectrum indicates that the radical responsible for 710-nm absorption is the 1-hydrobinaphthyl radical. This radical is formed through the bimolecular reaction between a naphthyl radical and a naphthalene molecule and is stable at room temperature in the crystalline lattice. 3 figures, 2 tables