Home – Home – Jornals – Atmospheric and Oceanic Optics 2015 number 1

The global modeling of the NO₂ central line positions has been performed within the framework of the method of effective operators. 195 parameters of polyad model of effective Hamiltonian have been fitted to 28 016 line positions collected from the literature in the 0.006-7916 cm^–1 wavenumber range. The global root mean square residual of the fit is 0.017 cm^–1. The used effective Hamiltonian takes explicitly into account both the spin-rotation interactions within each vibrational state together and numerous vibrational–rotational resonances. Indeed, because of approximate relations ω₁ ≈ ω₃ ≈ 2ω₂ between the three harmonic frequencies of NO₂, resonances due to first and second order C–type Coriolis interactions and to several Fermi and Darling–Dennison resonances had to be accounted for.