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The nitrogen and oxygen broadening coefficients of ozone have been experimentally obtained at two low temperatures (227 and 186 K) in the ν 1 + ν 3 band, located at 2110 cm −1 . Thirty-five transitions have been chosen to derive the n coefficient defined by α( T ) = α( T o )·( T o / T ) n . This is found, for both N 2 and O 2 , to be n = 0.72 ± 0.08, where 0.08 is two standard deviations. This value is accurate enough for atmospheric applications.

The infrared spectra of 16 O 3 have been recorded in the 3700 cm −1 region, with a Fourier transform spectrometer at 0.008 cm −1 resolution. A White-type cell,[formula]= 32.16 m, filled with 42.8 Torr O 3 was used. This spectral region corresponds to the ν 2 + 3ν 3 and ν 1 + ν 2 + 2ν 3 bands. The ν 2 + 3ν 3 band was observed and analyzed previously, but the interacting band ν 1 + ν 2 + 2ν 3 is observed for the first time. The assignments of this band cover the range J = 58, K a = 12; observations up to K a = 17 are available for ν 2 + 3ν 3 . The two states (013) and (112) are satisfactorily treated as a dyad, with a standard deviation of 1.5 × 10 −3 cm −1 for the 861 observed energy levels.

Using 0.003-cm −1 resolution Fourier transform spectra of 18 O-enriched ozone around 4.8 μm, the first high-resolution analysis of the ν 1 + ν 3 bands of 16 O 18 O 18 O and 18 O 16 O 18 O has been performed. The experimental rotational levels derived from the analysis were very satisfactorily calculated using a Hamiltonian model which takes into account the necessary interactions. More precisely, for 18 O 16 O 18 O, the Coriolis-type interactions coupling the levels of (101) with those of (002) and (200), as well as the Darling-Dennison interaction between (002) and (200), were considered. For the nonsymmetrical species 16 O 18 O 18 O, it proves necessary to include Coriolis-type interactions coupling the levels of (101) with those of (002) and (030). In this way, satisfactory fits were obtained, leading to the following band centers: ν 0 (ν 1 + ν 3 ) = 2060.0720 cm −1 for 18 O 16 O 18 O and ν 0 (ν 1 + ν 3 ) = 2027.5825 cm −1 for 16 O 18 O 18 O.

Using a Fourier transform spectrometer, we have recorded the spectra of ozone in the region of 4600 cm-1, with a resolution of 0.008 cm-1. The strongest absorption in this region is due to the nu1 + nu2 + 3nu3 band which is in Coriolis interaction with the nu2 + 4nu3 band. We have been able to assign more than 1700 transitions for these two bands. To correctly reproduce the calculation of energy levels, it has been necessary to introduce the (320) state which strongly perturbs the (113) and (014) states through Coriolis- and Fermi-type resonances. Seventy transitions of the 3nu1 + 2nu2 band have also been observed. The final fit on 926 energy levels with Jmax = 50 and Kmax = 16 gives rms = 3.1 x 10(-3) cm-1 and provides a satisfactory agreement of calculated and observed upper levels for most of the transitions. The following values for band centers are derived: nu0(nu1 + nu2 + 3nu3) = 4658.950 cm-1, nu0(3nu1 + 2nu2) = 4643.821 cm-1, and nu0(nu2 + 4nu3) = 4632.888 cm-1. Line intensities have been measured and fitted, leading to the determination of transition moment parameters for the two bands nu1 + nu2 + 3nu3 and nu2 + 4nu3. Using these parameters we have obtained the following estimations for the integrated band intensities, SV(nu1 + nu2 + 3nu3) = 8.84 x 10(-22), SV(nu2 + 4nu3) = 1.70 x 10(-22), and SV(3nu1 + 2nu2) = 0.49 x 10(-22) cm-1/molecule cm-2 at 296 K, which correspond to a cutoff of 10(-26) cm-1/molecule cm-2.