RYDBERG AND CHARGE-TRANSFER SLATES OF F-ATOMS IN NEON MATRICES

The interaction of an electronically excited F atom with the neon matrix is investigated using absorption, excitation, and fluorescence spectroscopy. Upon vacuum ultraviolet excitation of a neon matrix doped with fluorine atoms, emissions are observed at 12.80, 13.08, and 15.48 eV. The emissions at 13.08 and 15.48 eV have a lifetime of 0.7(0.2) ns and are assigned to the radiative relaxation of the 3s and 3s′ Rydberg F atomic states. The emission at 12.80 eV has a detection limited lifetime less than 0.4 ns and is identified as emission from the Ne+F- charge transfer complex. Absorption and excitation spectra of each of the observed emissions are used to identify the Rydberg absorptions of the F atoms perturbed by the neon matrix at 13.99, 16.27, 16.49, 16.94, 17.22, and 19.02 eV The Rydberg states belong to ns, ns′, and nd progressions with the same quantum defect as in the gas phase and a blueshift of the vertical ionization energies of 0.8 eV. The Stokes shift of 910 and 790 meV for the 3s and 3s′ states and the large linewidth are attributed to a strong electron phonon coupling with Huang-Rhys factors of about 70. A two-dimensional configuration coordinate model explains the observed absorption, excitation and emission spectra, and the branching ratios of emission from Rydberg and charge transfer states. © 1995 American Institute of Physics.