Ion-Molecule Reactions in Hydrogen Sulfide, Methane Thiol and 2-Thiopropane

摘要

The ion-molecule reaction in H2S, CH3SH, and (CH3)2S were observed at pressures up to 400 millitorr, using a quadrupole mass spectrometer with a single electron-impact ion source. Rate constants were measured for the disappearance of most primary ions and the appearance of several secondary ions, and mechanisms are proposed for the reactions observed. In all three cases, the major ion produced was the M + 1 ion (where M represents the mass of the parent ion), which reacted further to give the 2M + 1 ion. Charge exchange between the neutral gas and primary ions to produce the parent ion was observed in CH3SH and (CH3)2S and is suspected in H2S. In the cases of CH3SH and (CH3)2S, an additional reaction sequence originating with the (M - 1) ion was observed, while in H2S an additional sequence originating with the S(+) ion was found. (Author)