Stereo correlated dynamics in the energy transfer process of aligned N2 (A 3Σu +) + oriented NO (X 2Π, Ω = 1/2) → NO (A 2Σ+) + N2 (X 1Σg +) J. Chem. Phys. 137, 064311 (2012); 10.1063/1.4739273 Vibrationalstatetostate collisioninduced intramolecular energy transfer N2(A 3Σ u +, v'→B 3Π g , v') J. Chem. Phys. 98, 8606 (1993); 10.1063/1.464469 Double resonance studies of rotational energy transfer in the N2B3Πg state AIP Conf. Proc. 191, 664 (1989); 10.1063/1.38600Rotational transitions of N2(a 1Π g ) induced by collisions with Ar/He and N2(a 1Π g )-N2(X 1Σ+ g ) rovibronic energy transfer studied by laser REMPI spectroscopy

We have studied the state-to-state excitation of N2(B 3Πg, v′=1–11) in energy pooling reactions between N2(A 3∑+u, v′=0,1) molecules and subsequent quenching in collisions with molecular nitrogen. Excitation of vibrational levels 10, 2, and 3 appears to be much stronger than excitation of the other vibrational levels. In addition, we failed to observe any emission from v′=12 even though it is energetically accessible. The excitation rate coefficients are quite large, 7.7×10−11 cm3 molecule−1 s−1 for the pooling of two N2(A, v′=0) molecules, and roughly a factor of three larger for energy pooling events involving N2(A, v′=1). The effective rate coefficients for electronic quenching of N2(B) by N2 are also quite large, ≈3×10−11 cm3 molecule−1 s−1. Comparison of our quenching results with the laser-excited, real-time quenching studies of Rotem and Rosenwaks indicates agreement only within factors of 2–3.

Reaction rate constants for the quenching of electronic energy in metastable argon (3P0,2) by Kr, Xe, and a number of simple molecules have been measured. A hollow, cold-cathode discharge excites the metastables in a flow apparatus. The concentration of metastables was followed by absorption spectroscopy as a function of time and of quenching molecule concentration. Quenching of Ar*(3P2) by Kr, CO, N2, CF4, and H2(D2) proceeds at rates between 0.6 and 7 × 10−11 cm3 molecule −1 · sec−1. Except for Kr, Xe, N2, CO, and CH4, the 3P0 metastable level is quenched slightly more rapidly than the 3P2 level. With the aid of data in the literature, the contribution from the product channels (Penning and associative ionization) are considered for quenching by NO and C2H2. These channels appear not to be of major importance for quenching since the ionization efficiency of these two reactions is low: ∼ 0.2 for NO and ∼ 0.1 for C2H2. The quenching mechanism is discussed in terms of both a curve crossing and a ``golden rule'' rate law; the latter appears to be favored.

We have studied the formation of N2(C 3Πu, v=0–4) and the nitrogen Herman infrared system, v′=2,3, in energy pooling reactions between N2(A 3Σ+u, v′=0–1). Our results indicate rate coefficients of (1.5±0.4) and (1.5±0.5)×10−10 cm3 molecule−1 s−1 for formation of N2(C 3Πu, v′=0–4) from the energy pooling of two N2(A,v′=0) molecules and for a v′=0 and a v′=1 molecule, respectively. We did not see evidence of significant N2(C) formation in energy pooling between two N2(A,v′=1) molecules (k<5×10−11 cm3 molecule−1 s−1). N2(A,v′=0) energy pooling produces only v′=3 of the Herman infrared system with a rate coefficient of ≥(8.1±2.3)×10−11 cm3 molecule−1 s−1. Energy pooling between N2(A,v′=0) and N2(A,v′=1) produces only v′=2 of the Herman infrared system with a rate coefficient ≥(9.9±2.9)×10−11 cm3 molecule−1 s−1. Again, energy pooling between two N2(A,v′=1) molecules results in no significant contributions to the Herman infrared system. The participation of N2(A) vibrational levels ≥2, however, does result in excitation of the lower-lying vibrational levels of the Herman infrared system.

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