Single and double electronic transitions in molecular oxygen

Abstract

The emission bands at 6 340 Å and 7 030 Å in the spectrum of excited molecular oxygen, believed to be due to the "dimol" O4*(1Δg, 1Δg), have been investigated with respect to the dependence of their intensities on the excited oxygen concentration. The intensities of these bands have been shown, by a comparison with the intensity of the (0,0) band of the (1Δg – 3Σg−) system at 12 700 Å, to depend on the square of the O2(1Δg) concentration. The ratio of the intensities of the two visible bands at 6 340 Å and 7 030 Å was found to be 1.05 ± 0.1.An attempt was made to resolve the 6 340 Å and 12 700 Å bands into their rotational fine structure. The results show that, whereas the 12 700 Å band could be at least partially resolved, the 6 340 Å band appeared to be diffuse with a band half-width of 150 Å.Evidence is presented of vibrational excitation in the 1Σg+ state of molecular oxygen in the discharged products.