Rotational Satellite Intensities and Triplet Splitting in the B3Σu− State of S2

Measurements have been made on the intensities of rotational satellites (ΔN ≠ ΔJ) in selectively excited fluorescence in the B–X system of S2. The satellites appear in fluorescence emitted by the ν′ = 4 level but are absent in ν′ = 3 emission. Comparison of our results with line strengths calculated according to the formulation of Tatum and Watson shows that these two adjacent vibrational levels differ in the magnitude and sign of the triplet splitting constant. A reexamination of previous spectral analyses of the B–X system confirms this variation in coupling among B-state vibrational levels.