Knowledge Bank

The chemiluminescence resulting from the reaction of $O3$ with the simple sulfides, $CH3SH$ and $H2S$, has been studied at low pressures in a beam-gas apparatus. The fluorescence and vibrationally resolved phosphorescence from $SO\mathrm{<mrow\; data-mjx-texclass="ORD">\ast </mrow>}\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ produced in the reaction were monitored as a function of the pressure of the oxidizer, fuel and bath gas over a total pressure range from $5\times 10-3$ to $>10-1$ torr. The observed pressure dependencies provide estimates of the relative contributions of the long-lived $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}B1$ and short-lived $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}A2$ states to the total fluorescence band from $2800-5200$ \AA. The data also demonstrate that the $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}A2$ state is quenched to the triplet manifold and help to elucidate the mechanism for intersystem crossing in $SO2$. At longer wave lengths, structured emission for the reaction of $H2S$ is observed and is tentatively identified as HSO. For $CH3SH$ as the reactant, the meinel bands of DH are observed in the wave length region. These data are employed in developing a mechanism for the ozonolysis of these simple sulfides.