THE NO VIBRATIONAL FUNDAMENTAL BAND: TEMPERATURE DEPENDENCE OF $N_{2}$-BROADENING COEFFICIENTS

Abstract

Rovibrational spectra of the vibrational fundamental of nitric oxide have been recorded under $N_{2}$-broadening conditions at $0.0056 cm^{-1}$ resolution using the Solar McMath FTS at the Kitt Peak National Observatory. The temperature range for the experiments was 296 K to 183 K. The 30 cm absorption cell used for the measurements is cooled with a helium compressor and can operate at temperatures down to 60 K; vibration isolation of the cell allows its use with high performance Fourier Transform Spectrometers. From these Spectra, $N_{2}$-broadened line widths have been determined thru $|m| = 16.5$. Qualitative as well as quantitative discrepancies are observed between our experimental determinations of the temperature dependence of the broadening and theoretical calculations made by Houdeau et al. [J. Chem. Phys. 79, 1634 (1983)]. However, our measurements are in reasonable agreement with experiments carried out by Ballard et al. [J. Mol. Spectrosc. 127, 70 (1988)].