14604-48-9Relevant articles and documents
Ion - Molecule Reaction Studies of Hydroxyl Cation and Ionized Water with Ethylene
Fishman, Vyacheslav N.,Grabowski, Joseph J.
, p. 4879 - 4884 (1999)
Rate coefficients and product branching ratios for the ion - molecule reactions of the hydroxyl cation, ionized water, and their deuterated analogues with ethylene have been determined using a selected ion flow tube (SIFT) at room temperature and in 0.5 Torr of helium buffer gas. In all cases, reactions proceed at or near the collision rate. The major product is always charge transfer: 79% for L2O?+and 66% for LO+ and does not depend on the isotopic form of hydrogen present (L = H or D). For the L2O?+ reactions, the remaining 21% of products are from proton or deuteron transfer, with no evidence of an isotope effect on this step even in the HOD?+ reaction. The greater exothermicity of the initial charge transfer in the LO+ reaction is revealed by the observation of additional product channels, forming the vinyl cation and protonated carbon monoxide. Multistep mechanisms that proceed through rate-determining charge-transfer, followed by a product-determining step, are postulated to explain these observations.
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.
Selected-ion flow tube studies of reactions of the carbene cation :C4N+ and their implications for interstellar gas cloud chemistry
Bohme, Diethard K.,Wlodek, Stanislaw,Baksit, Asit B.
, p. 1563 - 1567 (2007/10/02)
The carbene cation :C4N+ was generated in a Selected-Ion Flow Tube (SIFT) apparatus from allyl cyanide by electron impact and related at room temperature in helium buffer gas at ca. 0.33 mm Hg with the molecules H2, CO, HCN, CH4, CD4, H2O, HC3N, C2H2, CH3CN, CD3CN, H2S, NH3, ND3, and C4H2.The reactions were observed to exhibit a range in reactivity and a variety of reaction products.The observed products are consistent with expectations based on the carbene caracter of :C4N+.The results have implications for the role of :C4N+ as a reaction intermediate in the chemistry of interstellar gas clouds.Possible synthetic routes indicated by :C4N+ are proposed for the formation of dicyanoacetylene, cyanodiacetylene, and several acyclic as well as cyclic neutral carbenes.
