Absorption and luminescence excitation spectra of ClF in the Vac UV region

Absorption and luminescence excitation spectra of ClF are recorded in the vacuum ultraviolet employing synchrotron radiation. A broad band (120–130 nm) due to transition to the ion-pair state E(0+) and sparse transitions to Rydberg states are observed. All Rydberg states are predissociated and their excitation yields no luminescence. Perturbations by the 4sσ1Π1 and 4pπ1Σ+ Rydberg states result in characteristic dips in the E(0+) state luminescence excitation spectrum. Excitation above the Cl∗ + F dissociation threshold results in luminescence from ion-pair states of ClF or Cl2 populated in reaction of Cl∗ with ClF or Cl2.