Nitrogen and oxygen broadening of ozone infrared lines in the 5μm region: theoretical predictions by semiclassical and semiempirical methods

Pressure broadening coefficients of the [image omitted] O3-N2(O2) vibrotational lines at room temperature were computed in the framework of the semiclassical formalism of Robert and Bonamy improved by exact trajectories, and a semiempirical approach based on the Anderson theory. In the first method, a more precise trajectory description enables a good (up to a few percent) reproduction of the experimental data available in the literature, but is characterized by a quite high CPU cost. In the second method, a simplified form of the scattering matrix accounts for the subtle effects of the trajectory curvature and vibrational dependence via effective adjustable parameters and noticeably reduces the CPU time without a loss of precision for further systematic computations. In contrast to the case of the water molecule, these parameters exhibit a quite pronounced dependence on the rotational quantum number J values of the lines used for fitting and should be properly adjusted for transitions from low, middle and high rotational levels.