Experimental observation of the F₂VUV laser levels

Abstract

The f 3 Pi g state of molecular fluorine, which is assumed to be the upper level of a VUV F2 laser at 157 nm, has been directly observed for the first time by high-resolution electron energy loss spectroscopy at low impact energies (less than about 30 eV) and large scattering angles. The new transitions consist of several vibrational components at 11.62, 11.75, 11.86 and 11.99 eV, and show every characteristic feature of spin-forbidden transitions.