Line broadening in the ν3 band of SO2 Studied with diode laser spectroscopy》.pdfVIP

JOURNAL OF MOLECULAR SPECTROSCOPY 152, I- 12 ( 1992) Line Broadening in the v3 Band of SO*: Studied with Diode Laser Spectroscopy F. KUHNEMANN, Y. HEINER,B.SUMPF,ANDKA.HERRMANN Humboldt-Universitit zu Berlin, Fachbereich Physik. AbteilungJiir Molekiilphysik/Photobiophysik, Berlin, Germany A spectrometer with pulsed lead salt diode lasers was used to study line broadening in the strongest band of S02, vj near 7.3 pm. A Fourier analysis technique was used to determine the linewidths; this technique increases the usablepressurerangefor closely spaced lines. The results give a decrease of both air- and self-broadening coefficients with increasing .I”and show an overall good agreement with theoretical data. 0 1992 Academic Pra, IX. INTRODUCTION High-resolution investigations of the rovibrational spectra of molecular gases are of growing interest. In addition to the fact that they provide experimental data for the determination of molecular parameters, they are essential for air pollution study and for atmospheric chemistry. A precise knowledge of line positions, strengths, and broadening coefficients and their temperature dependences is required for concentration measurements of atmospheric pollutants such as SOZ using in situ IR methods and for the prediction of atmospheric transmission. Line broadening of the SOZmolecule has been studied intensively in the microwave region (1, 2). Experimental data in the IR were reported by Hinkl