Cavity ringdown spectroscopy of the A˜-X˜ electronic transition of the phenyl peroxy radical

Cavity ringdown spectra (CRDS) of the near IR A∼2A′-X∼2A″ electronic transition of phenyl peroxy radical are reported. The electronic origin is observed at 7497 cm−1. Ab initio calculations have been carried out to aid the assignment of the electronic origin and other bands involving vibrational excitation.