New high-resolution analysis of the 3 nu(3) and 2 nu(1)+nu(3) bands of nitrogen dioxide (NO2) by Fourier transform spectroscopy

Using new high-resolution Fourier transform spectra recorded at the Univers ity of Denver in the 2-mu m region, a new and more extended analysis of the 2v(1), + v(3), and 3v(3), bands of nitrogen dioxide, located at 4179.9374 and 4754.2039 cm(-1) respectively, has been performed. The spin-rotation en ergy levels were satisfactorily reproduced using a theoretical model that t akes into account both the Coriolis interactions between the spin-rotation energy levels of the (201) vibrational "bright" state with those of the (22 0) "dark" state. The interactions between the (003) bright state with the ( 022) dark stare were similarly treated. The spin-rotation resonances within each of the NO, vibrational states were also taken into account. The preci se vibrational energies and the rotational, spin-rotational, and coupling c onstants were obtained for the two dyads [(220), (201)] and ((022), (003)) of the (NO2)-N-14-O-16 interacting states. From the experimental line inten sities of the 2v(1) + v(3) and 3v(3) bands, a determination of their vibrat ional transition moment constants was performed. A comprehensive list of li ne positions and line intensities of the (2v(1) + 2v(2), 2v(1) + v(3)) and the (2v(2) + 2v(3), 3v(3)) interacting bands of (NO2)-N-14-O-16 was generat ed. In addition, assuming the harmonic approximation and using the Hamilton ian constants derived in this work and in previous studies (A. Perrin, J.-M . Flaud, A. Goldman, C, Camy-Peyret, W. J. Lafferty, Ph. Areas, and C. P. R insland, J, Quant. Spectrosc. Radiat. Transfer 60, 839- 850 (1998)), we hav e generated synthetic spectra for the ((022), (003))-((040), (021), (002)) hot bands at 6.3 mu m and for the ((220), (201))-((100), (020), (001)) hot bands at 3.5 mu m, which are in good agreement with the observed spectra. ( C) 2000 Academic Press.