Kinetics and dynamics of near-resonant vibrational energy transfer in gas ensembles of atmospheric interest

This study of near-resonant, vibration–vibration (V–V) gas-phase energy transfer in diatomic molecules uses the theoretical/computational method, of Marsh & McCaffery (Marsh & McCaffery 2002 J. Chem. Phys. 117 , 503 ( doi:10.1063/1.1489998 )) The method uses the angular momentum (AM) theoretical formalism to compute quantum-state populations within the component molecules of large, non-equilibrium, gas mixtures as the component species proceed to equilibration. Computed quantum-state populations are displayed in a number of formats that reveal the detailed mechanism of the near-resonant V–V process. Further, the evolution of quantum-state populations, for each species present, may be followed as the number of collision cycles increases, displaying the kinetics of evolution for each quantum state of the ensemble's molecules. These features are illustrated for ensembles containing vibrationally excited N 2 in H 2 , O 2 and N 2 initially in their ground states. This article is part of the theme issue ‘Modern theoretical chemistry’.