THE ABSORPTION SPECTRUM OF CF₂

Abstract

The absorption spectrum of CF 2 in the 2 500 Å region has been photographed at high dispersion, and the rotational structure of a number of bands has been analyzed. The analysis of the well-resolved subbands establishes that these are perpendicular- rather than parallel-type bands, as previously assigned. Further analysis shows that the upper and lower electronic states are of 1 B 1 and 1 A 1 symmetries respectively, corresponding to a transition moment that is perpendicular to the plane of the molecule. In the upper electronic state, r 0 (CF) = 1.32 Å and [Formula: see text], while in the ground state, r 0 (CF) = 1.300 Å and [Formula: see text]. An investigation of the vibrational structure of the band system has shown that the vibrational numbering in ν 2 ′ must be increased by one unit from earlier assignments, thus placing the 000–000 band near 2 687 Å (37 220 cm −1 ). A search between 1 300 and 8 500 Å showed two new band systems near 1 350 and 1 500 Å which have been assigned tentatively to the CF 2 molecule.