Experimental observation of the F₂VUV laser levels

VUV Laser Spectroscopy of Trivalent Rare-Earth Ions in Wide Band Gap Fluoride Crystals

“…The energy position of the lower vibrational level of the 3 n 2g state was found to be 11.62 eV above the X'X g ground state [53], which is in agreement with theoretical calculations [54].…”

Environmental Research Division technical progress report: January 1986--October 1987

“…The 17.5-nm fluorescence observed between 11.6 and 12.89 eV can only come from the f 31 sate, because electron energy loss spectra show that this is the only state excited in this energy regime under the present experimental conditions (Hoshiba et al 1985). Scattered electron spectra of N 2 0 with 200-eV electrons have been recorded in an energy loss regime of 17 eV to 21 eV, corresponding to excitation from the 60 orbital.…”

“…This program of systematic measurements continues. By using variable-energy, high-resolution electron impact techniques, we have directly observed for the first time the emission of 157.5-nm "laser" photons from the f 3n state of F 2 1, which has long been conjectured to be (Woodworth and Rice 1978), though only recently was energetically located in (Hoshiba et al 1985), the upper laser level in molecular fluorine. The results of our experiments are shown in Fig.…”

“…each of which corresponds energetically with the known location of one of four electronic states of F 2 . These states are the f 31 state located by Hoshiba et al (1985) at 11.62 eV, the CDE 1+ states at 1Z.85 eV (colbourne et al 1976), an unidentified transition observed at 14.0 eV by Hoshiba et al (1985), and the I1Eu state at 14.127 eV (Colbourne et al 1976). The background level corresponds on an average to about 8 photons per channel, which translates to about 1 dark photon per 10 seconds.…”

Spectroscopy of F2 in Ne matrices

“…5 The vibrational levels of the C 1 ⌺ u ϩ state in the region around 12.5 eV are resolved in the optical spectrum while the EEL spectrum shows mainly the Franck-Condon envelope. Four vibrational bands of the H 1 ⌸ u state are seen in both spectra between 13.1 and 13.5 eV and a fifth band at 13.613 eV in Fig.…”