Infrared Spectroscopy of H₂S and SH in Rare-Gas Matrixes

Infrared (IR) spectra of hydrogen sulfide (H2S), some of its complexes, and their photolysis products are studied in rare-gas matrixes (Ar, Kr and Xe) at 7.5 K. In all of these matrixes, H2S is found to undergo hindered rotation. The vibration−rotation structures of monomeric H2S are observed at 2651−2615, 2640−2600, and 2625−2580 cm-1 in Ar, Kr, and Xe matrixes, respectively. Furthermore, the H2S dimer and the H2S···H2O complex are observed in various matrixes. Upon UV-induced decomposition of H2S, IR absorptions of SH radical appear at 2607 cm-1 (Ar) and 2594 cm-1 (Kr). The SH radical is also observed to be complexed with H2S (2563, 2553, and 2550 cm-1 in Ar, Kr, and Xe, respectively) and water (2556 cm-1 in Kr).