Reactive scattering of ground-state and electronically excited oxygen atoms on a liquid hydrocarbon surface

1997 ◽  
Vol 108 ◽  
pp. 387-399 ◽  
Author(s):  
Donna J. Garton ◽  
Timothy K. Minton ◽  
Michele Alagia ◽  
Nadia Balucani ◽  
Piergiorgio Casavecchia ◽  
...  
Keyword(s):  
Ground State ◽  
Liquid Hydrocarbon ◽  
Reactive Scattering ◽  
Electronically Excited ◽  
Excited Oxygen ◽  
Oxygen Atoms

The collisional quenching of electronically excited oxygen atoms, O(21D2), by the gases NH3, H2O2, C2H6, C3H8, and C(CH3)4, using time-resolved attenuation of atomic resonance radiation

1976 ◽  
Vol 54 (11) ◽  
pp. 1765-1770 ◽  
Author(s):  
I. S. Fletcher ◽  
D. Husain
Keyword(s):  
Resonance Radiation ◽  
Recent Measurement ◽  
Absolute Rate ◽  
Collisional Quenching ◽  
Time Resolved ◽  
Excited Atoms ◽  
Electronically Excited ◽  
Hartley Band ◽  
Excited Oxygen ◽  
Oxygen Atoms

A kinetic study of electronically excited oxygen atoms, O(21D2), is presented. These optically metastable species were generated by repetitive pulsed irradiation in the Hartley-band continuum and monitored photoelectrically in absorption by time-resolved attenuation of resonance radiation at λ = 115.2 nm (O(31D20)←O(21D2). Absolute rate constants for the collisional quenching of O(21D2) are reported for the gases NH3, H2O2, C2H6 C3H8, and C(CH3)4. These are found to be respectively (in units of 10−10 cm3 molecule−1 S−1 at 300 K), 6.3 ± 0.7, 5.2 ± 0.6, 7.3 ± 0.8, 9.5 ± 1.0, and 12.3 ± 1.3. With the exception of a recent measurement for NH3• these data represent the first absolute measurements for these quenching gases. Further, a general comparison is made between absolute rate measurements using this technique and recent work by Schiff and co-workers using time-resolved emission at λ = 630 nm (O(21D2) → O(23P2)) in order to monitor the excited atoms.

Branching ratios for electronically excited oxygen atoms formed in the reaction of N+ with O2 at 300 K

1986 ◽  
Vol 84 (4) ◽  
pp. 2158-2166 ◽  
Author(s):  
Andrew O. Langford ◽  
Veronica M. Bierbaum ◽  
Stephen R. Leone
Keyword(s):  
Branching Ratios ◽  
Electronically Excited ◽  
Excited Oxygen ◽  
Oxygen Atoms

Excited State Chemistry in the Stratosphere

1974 ◽  
Vol 52 (8) ◽  
pp. 1452-1464 ◽  
Author(s):  
R. J. Cvetanović
Keyword(s):  
Excited State ◽  
Excited States ◽  
Chemical Behavior ◽  
Molecular Fragments ◽  
Electronically Excited ◽  
Excited Oxygen ◽  
Oxygen Atoms

Potential involvement of excited states of molecules and molecular fragments in the chemistry of the stratosphere is discussed, with particular emphasis on the chemical behavior of electronically excited oxygen atoms.

Collisional quenching of electronically excited oxygen atoms, O(1D): temperature dependence of some rate coefficients

1976 ◽  
Vol 5 (3) ◽  
pp. 173
Author(s):  
G.E. Street ◽  
C.J. Howard ◽  
A.L. Schmeltekopf ◽  
J.A. Davidson ◽  
C.M. Sadowsky ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Rate Coefficients ◽  
Collisional Quenching ◽  
Electronically Excited ◽  
Excited Oxygen ◽  
Oxygen Atoms

The kinetics and mechanism of the reaction of atomic oxygen with acetylene

1973 ◽  
Vol 335 (1603) ◽  
pp. 547-562 ◽  
Keyword(s):  
Triplet State ◽  
Rate Constant ◽  
Ground State ◽  
Excited Molecule ◽  
Secondary Process ◽  
Experimental Conditions ◽  
Electronically Excited ◽  
Stable Product ◽  
State Concentration ◽  
Oxygen Atoms

A photoionization mass spectrometer has been used to study the reaction of ground-state oxygen atoms with acetylene. The oxygen atoms were produced in the absence of molecular oxygen in a discharge-flow system with nitrogen as the principal carrier gas. Several of the free radicals and stable product molecules that were observed previously have been studied in more detail. Experiments with added gases have shown that the methylene radicals observed are probably in their ground, triplet state. The ratio of rate constants for the reactions of CH 2 with O 2 and O respectively was found to be approximately 1:10. The dependence of the C 3 H 3 radical concentration on the experimental conditions showed that C 3 H 3 was formed in a secondary reaction, probably involving an excited molecule or radical. The rate constant for the reaction of the HCCO radical with O 2 was measured as 2.2 ± 1.2х10 7 1 mol -1 s -1 . The product observed at mass 42 appears to be ground-state ketene formed in the primary step, perhaps via a triplet state. However, the possibility that the ketene might be formed in a secondary process cannot be dismissed. The rate constant for the reaction of ground-state oxygen atoms with ketene was measured, with a result significantly lower than a previous study. The diacetylene concentration showed a complex dependence on reaction conditions. Analysis of the approach of [C 4 H 2 ] to its steady-state concentration gave a rate constant for the reaction of oxygen atoms with diacetylene of 1.6 ± 0.5 х10 9 1 mol -1 s -1 . The relation of these results to previous studies is discussed briefly. It is suggested that a reaction of one or more of the energetic primary products, such as electronically excited CH 2 , HCCO or ketene, could be responsible for the chemiluminescence of CH, OH and CHO.

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