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A step-scan Fourier-transform spectrometer coupled with a 6.4-m multipass absorption cell was employed to detect time-resolved infrared absorption spectra of reaction intermediates produced upon UV irradiation of a flowing mixture of CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SSCH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$ and NO$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ in CO$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$. Irradiation of CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SSCH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$ at 248 nm produces CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$S radicals that subsequently react with NO$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$. Under a total pressure of 100 Torr, we observed bands near 1560 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$, assignable to mainly the N=O stretching mode of CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SONO, with a small contribution from CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SNO$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$. Calculations with density-functional theory (B3LYP/aug-cc-pVTZ and B3P86/aug-cc-pVTZ) predicted the geometry, vibrational wavenumbers, and rotational parameters of CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SONO and CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SNO$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$. Based on these predicted rotational parameters, the simulated absorption band agrees satisfactorily with experimental results. Under a total pressure of 16 Torr, bands near 1560 and 1260 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$ are assigned to NO$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ asymmetric and symmetric stretching modes of CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SNO$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$, respectively; the former is overlapped with the N=O stretching mode of CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SONO. An additional band near 1070 cm$\mathrm{<mrow\; data-mjx-texclass="ORD">-1</mrow>}$ is assigned to the S=O stretching mode of CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SO, reported previously as a secondary product in the reaction of CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$S + O$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$. nderline{133}, 184303 (2010).} Reaction of CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$S + NO$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ at high pressure clearly yields CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SONO, rather than CH$\mathrm{<mrow\; data-mjx-texclass="ORD">3</mrow>}$SNO$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$, as a major product.