Infrared spectra of two isomers of protonated carbonyl sulfide (HOCS+and HSCO+) and t-HOCS in solid para-hydrogen.
We report infrared (IR) spectra of HOCS+, HSCO+, t-HOCS, and other species produced on electron bombardment of a mixture of carbonyl sulfide (OCS) and para-hydrogen (p-H2) during deposition at 3.2 K. After maintenance of the matrix in darkness for 15 h, the intensities of absorption features of HOCS+at 2945.9 (ν1), 1875.3 (ν2), and 1041.9 (ν3) cm-1and those of HSCO+at 2506.9 (ν1) and 2074.2 (ν2) cm-1decreased through neutralization with trapped electrons. Lines observed at 3563.4, 1394.8, and 1199.0 cm-1, which decreased slightly in intensity after maintenance in darkness and were nearly depleted after irradiation at 373 nm, are assigned to a t-HOCS radical. The corresponding spectra of their13C- and D-isotopologues were observed. The IR spectra of HSCO+and t-HOCS and those of modes ν2and ν3of HOCS+are new. The assignments were made according to the expected chemical behavior and a comparison of experimental and calculated wavenumbers and13C- and D-isotopic shifts. The wavenumber of the OH stretching mode (2945.9 cm-1) of HOCS+in solid p-H2is significantly red-shifted from that (3435.16 cm-1) reported for gaseous HOCS+; this shift is attributed to partial sharing of a proton between OCS and H2. The corresponding p-H2induced shift is small in HSCO+because of a much weaker interaction between HSCO+and H2.
Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
Masashi
M
Tsuge
Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, 1001 Ta-Hsueh Road, Hsinchu 30010, Taiwan.
Yuan-Pern
YP
Lee