Rydberg and charge transfer states of F atoms in neon matrices

Abstract

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 0.7͑0.2͒ ns and are assigned to the radiative relaxation of the 3s and 3sЈ 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 ϩ F Ϫ 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, nsЈ, 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 3sЈ 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.

Feynman Force Analysis of Chemical Processes in Terms of Topological Atomic Contributions

“…The potential energy curves for the ground and low-lying excited states of Ne 2 and NeF are shown in Figure S1, which are relevant to describe the formation of the excited states complexes. The general features of these PECs agree with those of previous reports. − The Ne 2 excimer has a much larger binding energy than the ground state complex because of the different types of interactions involved which are van der Waals in the ground state and covalent in the excimer . In the case of NeF, the ground state complex dissociates to the neutral atoms and the exciplex remains ionic (Ne + F – ) along the PEC.…”

Penetration depth of photomobilized F atoms in Ar layers from a sandwich experiment

“…26 For lower energies, exciplexes of fluorine with rare gas atoms are generated, and the emission of trimers prevails compared to dimers due to the lower energies 3,27 similar to the heavier halogens. 3 The emission energies of Rg 2 F trimers, formed with different rare gas atoms Rg, reflect the ionization energies of the rare gas atoms since charge transfer states are involved.…”

Spectroscopy of F2 in Ne matrices

“…6͒. The matrix shift in Ne amounts for Rydberg states of F atoms to 0.75 eV, 20 of Cl 2 to about 1 eV 10 and of NO to 1.3 eV ͑Ref. 7͒ together with a significant broadening of these bands.…”