14531-53-4Relevant articles and documents
Reactions of He+, Ne+, and Ar+ with CH4, C2H6, SiH4, and Si2H6
Chatham, H.,Hils, D.,Robertson, R.,Gallagher, A. C.
, p. 1301 - 1311 (1983)
The rate coefficients and product-ion distributions for the reactions of He+ and Ar+ with silane and disilane have been measured in a drift tube, typically for collision energies of 0.01-1 eV.The total charge-exchange rate coefficients are found to be roughly independent of E/N, or collision energy, and are about equal to the Langevin values for the reactions of He+ with SiH4 and C2H6 and Ar+ with CH4 and C2H6.The He+ rate coefficients on CH4 and Si2H6, and the Ne+ rate coefficients on SiH4 and Si2H6 are 50percent to 80percent of the Langevin values, while the Ar+ rate coefficients on SiH4 and Si2H6 are much smaller.Product ions tend to be hydrogen poor with very infrequent breaking of the C-C or Si-Si bonds.Furthermore, hydrogen stripping is more severe for the silanes than the alkanes.These product-ion distributions bear no resemblance to the product-ion distributions of either photoionization or electron collisional ionization.
Dissociation dynamics of CH4+ core ion in the 2A1 state
Furuya, Kenji,Kimura, Katsumi,Sakai, Yasuhiro,Takayanagi, Toshinobu,Yonekura, Nobuaki
, p. 2720 - 2728 (1994)
Threshold-photoelectron photoion coincidence (TPEPICO) spectra of CH4 have been observed with synchrotron radiation at the excitation to the 2A1 (υ1=0-3) ionic states as well as to the 4pt2 Rydberg (υ1 = 0-4) states.In all the TPEPICO spectra observed, the CH3+ band shape was almost rectangular, which suggests that the translational and internal energy distributions of CH3+ are very narrow.The total kinetic energy releases (KERs) have been estimated from the CH3+ band shape.As a result, it was found that the CH3+ species were in an electronically excited state.There was a narrow distribution of the total KERs and similarity in the TPEPICO CH3+ band shapes between the spectra at the 2A1 ionic state and the 4pt2 Rydberg state excitations, which led to the conclusion that the Rydberg electron is just a spectator and the dissociation of the core ion plays an important role in dissociation through the 4pt2 Rydberg state.Similar results have also been obtained for CH2+ and CH+ productions.However, on the other hand, an H+ fragment has been observed only at the 2A1 state excitation.It showed a band with a long tail in the slower flight time region.The total average KERs and the decay rates have been estimated from band shape simulation.From these results, it has been found that a dissociation limit of the H+ ion exists just below the 2A1 ionic state.The dissociation mechanisms through the 4pt2 Rydberg state have been discussed in detail in comparison with those of the 2A1 ionic state.
Dissociative photoionization of CH3SSCH3 in the region of ～8-25 eV
Chiang, Su-Yu
, p. 9056 - 9063 (2007/10/03)
The dissociative photoionization of CH3SSCH3 has been investigated in the photon energy range of ～8-25 eV with a molecular beam/photoionization mass spectrometry/threshold photoelectron spectrometry system using synchrotron radiation as an ionization source. For dissociation above photon energy of 11.5 eV, six fragment ions of CH3+, C2H3+, SH3+, HCS+, S2+, and CH2S2+ were reported for the first time. The photoionization efficiency spectra for the parent ion and for 12 observed fragment ions, CH3+, C2H3+, SH3+, HCS+, CH2S+, CH2SH+, CH3SH+, CH3SH2+, CH3SCH2+, S2+, CH2S2+, and CH2S2H+, were measured; their branching ratios as a function of photon energy were derived. Ionization energy of 8.20±0.04eV for CH3SSCH3 and the appearance energy for each fragment ion were determined from the onsets of the photoionization efficiency spectra. Based on the appearance energy and existing thermochemical data, plausible structures of the fragment ions and their neutral counterparts are proposed. Fragmentation mechanisms that involve H migration and structural rearrangement in the dissociative photoionization processes are discussed.
