Knowledge Bank

Both natural abundance sulfur and 50% enriched $\mathrm{<mrow\; data-mjx-texclass="ORD">34</mrow>}S$ were used to make $S2$ vapor at $\sim 600K$ and $\sim 10-2$ torr in dual–temperature sealed quartz cells. The fluorescence excited by both a CW He-Cd laser ($\nu vac=30757.5cm-1$) and a pulsed nitrogen laser (29652 -$29661cm-1$) was dispersed and analysed to identify the fluorescing quantum state (s). For He-Cd excitation, normal and isotopically enriched samples gave identical results: only a single transition in $\mathrm{<mrow\; data-mjx-texclass="ORD">32</mrow>}S2$ was excited: $B3\Sigma u--,v\prime =3,N\prime =J\prime =24\leftarrow X3\Sigma -g,v\prime \prime =3,N\prime \prime =J\prime \prime =25,\nu =30757.19cm-1$ (see Ref. 1) For $N2$ excitation it appears that several regular and satellite lines in the 2,4 $band2$ in the vicinity of $J\prime \prime =25-28$ are pumped. A reanalysis of existing spectroscopic data for $S2(B-X)$ is in progress, and will be discussed.