Multiphoton dissociation/ionisation of dimethyl sulphide (CH3SCH3) at 355 and 532 nm
نویسندگان
چکیده
Multiphoton dissociation/ionization has been studied for CH3SCH3 at 355 and 532 nm using a time-of-flight mass spectrometer. The major ion signals observed at 355 nm are C, CH3 , HCS, CH2S , CH3S + and CH3SCH3 . Power dependence studies at 355 nm show a (2 + 1) REMPI process for the formation of parent ion. Peaks at m/e = 46, 47 and 61 show two-photon laser power dependence whereas m/e = 15 and 45 peaks show four-photon dependence. However, in 532 nm photoionisation, no parent ion signal is observed. A peak at m/e = 35 corresponding to SH3 + has been observed. SH3 + has been suggested to originate from CH3SCH2 + via a cyclic transition state. Photoionisation results of CH3SCH3 have been compared with those of CH3SSCH3, at these two wavelengths.
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