Absolute rate constant determinations for the deactivation of O(1D) by time resolved decay of O(1D) →O(3P) emission

Abstract

Rate constants for the deactivation of O(1 D) by Xe, Kr, and Ar over the range 110-330 K Determination of absolute rate constants for an excited triplet state Absolute rate constants for the deactivation of OeD) atoms by some atmospheric gases have been determined by observing the time resolved emission of OeD) at 630 nm. OeD) atoms were produced by the dissociation of ozone via repetitive laser pulses at 266 nm. Absolute rate constants for the relaxation of OeD) (x 10-10 cm 3 molecule-I. S-I) by N 2 (0.Ne «0.0013) are reported at 298 K. The results obtained are compared with previous relative and absolute measurements reported in the literature.

Energy partitioning in O(1D2) reactions. III. O(1D2) + NH3 → OH(v′) + NH2

“…It is less likely to have caused the increased vibrational excitation in the present case, however, because it is not possible to sustain a large excess of O('Dz) atoms until the necessary concentration of NH2 radicals has been generated. The rate constants for the reaction of 0 ( ' D 2 ) with both NH3 and O3 are approximately gas kinetic (3 X l o C L 0 and 2 x lo-'' cm3 moleculeC1 sC1, respectively) (2,18) and thus virtually no 0('D2) will remain after the first two or three gas kinetic collisions following the ozone photolysis. Its rapid disappearance while the NH2 is being formed thus reduces the importance of the secondary reaction.…”

Development of a stable source of atomic oxygen with a pulsed high-voltage discharge and its application to crossed-beam reactions

“…The feature with maximum near 12.7 eV is assigned to transitions from the 1 D state to several autoionizing states of oxygen atoms, whereas the feature having a threshold about 13.6 eV is assigned to transitions of 3 P oxygen atoms. The rate coefficient for the relaxation of 1 D O atoms by O 2 molecules was reported to be ͑4.1± 0.5͒ ϫ 10 −11 cm 3 molecule −1 s −1 at 298 K. 16 Employing relative photoionization cross sections of 3 P and 1 D oxygen atoms, 17 we determined the ratio 1 D / 3 P to be 0.042, 0.007, and 0.002 for mixtures of 3%, 10%, and 20% O 2 seeded in He, respectively, at a discharge current ϳ30 mA. …”

Towards a Consistent Chemical Kinetic Model of Electron Beam Irradiation of Humid Air

“…Mätzing's model included the decay of O( 1 D) to ground state atomic oxygen by emission. This spin-forbidden process was deleted because it is much slower than several chemical reactions [26]. Three reactions involving excited state atomic oxygen clustered to either H 2 O, NH 3 , or O 3 were deleted because neither Mätzing nor any other source provided rate constants for formation of the clusters.…”