Vibrational-state-specific total-removal relaxation rate constants, kv(M), for O2(X 3Σ−g, v=15 to 26) by M=CO2, N2O, and N2 have been obtained using the stimulated emission pumping (SEP) method in a pump–dump and probe configuration. Relaxation by O3 was studied using the chemical activation method, where the reaction: O(3P)+O3→O2(v)+O2, was employed to produce highly vibrationally excited O2 in an excess of ozone. Efficient (1%–2% of the gas kinetic limit) near-resonant 2–1 and/or 1–1 vibration-to-vibration (V–V) energy exchange was observed whenever the energy resonant condition was fulfilled and the transition in the quench partner would have been an allowed infrared transition in the isolated molecule. For M=CO2 and N2O, the temperature dependence of the 2–1 near-resonant energy transfer rate constants was found to be inverted. In contrast, the temperature dependence of the V–R, T relaxation rate constants for M=O2 was normal. For M=N2, a weak but positive temperature dependence was found. By extrapolating the temperature dependence to mesospheric temperatures (200 K) the effect of highly vibrationally excited O2 on the thermal budget can be discussed. The rate constant for the reaction of O(3P)+O3 was determined for an elevated collision energy of ∼10 kcal/mol and was found to be 5000 times larger than the room temperature rate constant.

The CH(X 2Π,v,J,Ω,Λ) product state distribution from the reaction C(1D)+H2(v)→CH+H was determined by laser-induced fluorescence (LIF) where the B 2Σ–X 2Π transitions were probed. Most of the available energy is released as translation. A nearly thermal rotational distribution is obtained for CH(v=0,1). Only a small fraction, 4.1×10−4, of the CH products is formed in the vibrationally excited state. A higher propensity for the production of CH in the symmetric Π(A′) Λ sublevels is evident. For studying the influence of vibrational excitation on the reaction dynamics, H2 was excited to its first vibrational state via stimulated Raman pumping (SRP). H2(v=1) increases the reaction rate and enhances the population of higher rotational states, but diminishes the Λ selectivity. The vibrational population ratio P(v=0)/P(v=1) of the CH product remains unaltered. Insertion of the C(1D) atom into the H2 bond is the major reaction mechanism, but the probability for an abstractive process seems to increase when H2(v=1) is reacting with C(1D).

Dynamics of the N(4 S u )+NO(X 2Π)→N2(X 1Σ+ g )+O(3 P g ) atmospheric reaction on the 3 A' ground potential energy surface. II. The effect of reagent translational, vibrational, and rotational energies Effects of translational, rotational, and vibrational energy on the dynamics of the D+H2 exchange reaction. A classical trajectory study J. Chem. Phys. 94, 7991 (1991); 10.1063/1.460133 A multisurface DIM trajectory study of the reaction: O(1 D g )+H2(X 1Σ+ g )→OH(X 2Π)+H(2 S) J. Chem. Phys. 88, 3629 (1988); 10.1063/1.453913 Rational fraction representation of diatomic vibrational potentials. V. The 3dσ g state of H+ 2The OH product state distribution from the reaction OeD) + H2 (v) --+OH(v",J" ,n,A) + H was determined by laser-induced fluorescence (LIF) in the Av = -3 band for v" = 3 and 4 with resolution of the J ", n, and A sublevels. The rotational state population distribution is inverted strongly in v" = 3, weaker in v" = 4. There is a higher propensity for production of OH in the Il(A') A-sublevels. Vibrationally excited H2 was used for a part of the experiments. Excitation was achieved by stimulated Raman pumping (SRP). The population ratio of the vibrational states was determined to be P(v = 3 )IP(v = 4) = 3.5 for the reaction with H2 (v = 0) and 3.0 when there is H2 (v = 1) in the reaction chamber. Higher OH product states are populated than it would be expected from the mean available energy of the reaction. The translational energy of the reactants is transferred into OH rotation.

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