Line-mixing effects in the rotational (r)Q-branches of O-16(3) perturbed by N-2 and O-2

Line-mixing effects have been studied in the (r)Q(5) to (r)Q(12) rotational subbranches of O-16(3). Far-infrared Fourier transform measurements have been made in the 30-90 cm(-1) spectral region for mixtures of ozone with N-2 and O-2 at room temperature and total pressures in the 0.5-1.3 arm range. A careful analysis of the experimental data evidence, for the first time, the effects of line interferences on absorption in the far-infrared ozone branches. Modifications with respect to additive Lorentzian line contributions are on the order of 15% at the (r)Q(Ka) peaks under atmospheric conditions. A simple model is proposed in order to account for these line-mixing effects. It successfully predicts the spectral shape in the 0.05-1.3 atm total pressure range for both O-3-O-2 and O-3-N-2 collisions. (C) 1996 Academic Press, Inc.