The 2nu1 + nu2 + 3nu3 Band of 16O3: Line Positions and Intensities.

The 2nu1 + nu2 + 3nu3 band of ozone, which occurs in the 5700-cm-1 region, has been observed for the first time using a Fourier Transform Spectrometer, operating at 0.008 cm-1 resolution and with a large pathlength x pressure product (3216 cm x 28.3 Torr). The assignment of rotation-vibration transitions has been done for J up to 38 and Ka up to 11, respectively, after many difficulties due to a Coriolis coupling between (213) and (420) states. In this work we show how this one, which occurs between closed band centers (4 cm-1) but corresponds to summation operatoriDelta vi = 6, strongly perturbs energy levels and leads to a difficulty in assignments. In particular we show the deviations for various types of J and Ka as large as 1 cm-1, with respect to the calculations performed without account of this resonance. The final calculation for the 212 rovibrational states is very satisfactory, as the r.m.s. is 2.5 x 10(-3) cm-1, near the experimental accuracy, with meaningful spectroscopic Hamiltonian parameters. Rovibrational lines intensities of the 2nu1 + nu2 + 3nu3 band were measured, and the value of the transition moment has been recovered. Finally a complete list of line positions and intensities was calculated (with a cut-off of 3 x 10(-26) cm-1/molecule cm-1) leading to a total band intensity of Sv = 3.118 10(-23) cm-1/molecule cm-2 at 296 K. Copyright 1998 Academic Press.