Line Positions and Intensities of the ?1 + 2?2 + ?3 and 2?2 + 2?3 Bands of 16O3

Abstract A study of high-resolution (0.006 cm −1 ) Fourier transform absorption spectra of 16 O 3 around 3450 cm −1 has been performed, leading to the first analysis of the ν 1 + 2ν 2 + ν 3 and 2ν 2 + 2ν 3 bands of this molecule. To increase the absorption strength of these very weak bands a White cell with path lengths of up to 36 m and pressures from 40 to 55 Torr was used. The rotational energy levels of the (121) and (022) vibrational states deduced from observed spectra have been satisfactorily reproduced using a Hamiltonian matrix which takes explicitly into account the Coriolis interaction between (121) ↔ (022) and (121) ↔ (220) and Darling-Dennison interaction between (022) ↔ (220). Furthermore about 60 and 20 line intensities, respectively, for the (121) and (022) bands were measured with an accuracy of about 6 and 12%, leading to the determination of the ν 1 + 2ν 2 + ν 3 and 2ν 2 + 2ν 3 vibrational transition moments. Finally, a complete list of line positions, intensities, and lower state energies for both bands has been generated.