87191-90-0Relevant academic research and scientific papers
Dissociation dynamics of C3O2 excited at 157.6 nm
Strauss, C. E. M.,Kable, S. H.,Chawla, G. K.,Houston, P. L.,Burak, I. R.
, p. 1837 - 1849 (1991)
The dissociation of carbon suboxide by single photon absorption at 157.6 nm has been studied under the collisionless environment of a molecular beam.The primary products are 2CO + C 3P(97percent) or 1D(3percent)>.The spin-orbit levels of the 3P carbon are statistically distributed.The CO rotational populations in the first four vibrational levels are found to be well described by Boltzmann distributions with temperatures 3430, 4120, 4670, and 2340 K for v = 0,1,2,3, respectively.A second low temperature component in the v = 0 rotational distribution is attributed to CO produced in coincidence with C(1D).Significant population is found in the first four vibrational levels with less than 3percent estimated in the higher levels; a vibrational temperature of 3700 K fits the distribution.Analysis of the Doppler profiles of the CO and carbon suggest that the dissociation is stepwise; the first dissociation appears to be described by an anisotropy parameter near β = 2, while the second appears to be isotropic.The mean CO fragment speeds were nearly constant for all rotational levels, though slightly faster for v = 1 than v = 0.From the translational energetics of the CO at least a small amount of stable C2O is inferred to exist.The overall energetics place the stable C2O quantum yield under 2percent assuming that excited C2O is not radiatively stabilized.We were unable to detect C2O directly in any electronic state.The dissociation of C3O2 into C(3P) + 2CO appears to be best described as a stepwise reaction that produces a nearly statistical partitioning into all fragment degrees of freedom.The best agreement is obtained for an intermediate C2O electronic state in the vicinity of the b state (e.g., b, >a or >A); a ground state C2O intermediate is unlikely.The singlet to triplet crossing most likely occurs in the C2O system on a time scale longer than a rotation (a few picoseconds).
Kinetics of the C2(a3IIu) radical reacting with selected molecules and atoms
Becker,Donner,Freitas Dinis,Geiger,Schmidt,Wiesen
, p. 503 - 517 (2007/10/03)
Rate coefficients for reactions of the C2 radical in its a3IIu electronic state with H, N and O atoms and with C3O2, C4F6, H2, NO, N2O, C2H2, C2H4, C3 H4 and C6H6 were determined. This work represents the first study of reactions of C2(a3IIu) radicals with the atoms investigated at room temperature and 4 Torr total pressure. The bimolecular rate constants obtained for the atom reactions were kc2+o = (9.8 ± 1.0) × 10-11- , kc2+N = (2.8 ±1.0) × 10-11 and kc2+N-14, in units of cm3 s-1. In addition, the reaction C2 + O was found to be independent of total pressure in the range 2-60 Torr. For the reaction C2(a3IIu) + ethene (C2H4) a temperature and pressure independent rate constant of (9.5 × 1.2) × 10-11 cm3 s-1 was obtained in the temperature range 298-1000 K at 100 Torr total pressure and in the pressure range 5-100 Torr at 298 K. The following rate constants were determined at room temperature and a total pressure of 4 Torr for the reactions of C2(a3IIu) radicals with benzene (C6H6), acetylene (C2H2) and allene (C3H4): kc2+C6H6 = (4.9 ± 0.1) ×10-10, kc2+C2H2 = (1.0 ± 0.1) ± 10-10 and kc2+C3H4 = (1.9 ± 0.3) ×10-10, in units of cm3 s-1. The reaction C2 + NO was investigated at room temperature and 100 Torr total pressure, a rate constant kc2+NO = (6.8 ± 0.3) × 10-11 cm3 s-1 was obtained. The reaction C2 + N2O was studied at 4 Torr total pressure in the temperature range 300-700 K for which a temperature independent rate constant kc2+N2O = (3.1 ± 0.4)X 10-14 cm3 s-1 was determined. by Oldenbourg Wissenschaftsverlag, Muenchen.
Isomers and reactivity of C3N+: An experimental study
Petrie, Simon,McGrath, Kathryn M.,Freeman, Colin G.,McEwan, Murray J.
, p. 9130 - 9136 (2007/10/02)
The C3N+ ion, generated by electron impact on HC3N and C4N2 and as a product in several ion-molecue reactions, was found to exist in two isomeric forms: CCCN+ and cylic C3N+. These forms were distinguished by their different reactivities with a range of neutral reagents in a selected-ion How tube (SIFT). Isomeric identification was made by reference to existing ab initio calculations. The most reactive isomer, CCCN+, was the major form (≥90%) of the C3N+ ion from all sources of production examined and was found to undergo collision-rate reactions with most of the neutral molecules studied c-C3N+ was much less reactive, which implies an activation barrier in its reactions as it is the higher energy form. Product distributions are reported for the reactions of CCCN+, and rate coefficients for the reactions of both isomers with H2, CH4, NH3, M2O, N2, O2, CO, C2H2, HCN, CO2, and C2N2 at 300 ± 5 K are also given.
