Anhydrous nitric acid integrated absorption cross sections:: 820-5300 cm-1

Fourier transform infrared absorbance measurements of small aliquots of anhydrous nitric acid were used to determine regional, integrated cross sections at 278.2, 298.22 and 323.15 K. Spectra were recorded with pressure broadened samples (I atmosphere nitrogen), in a 20 cm path length cell at a spectral resolution of 0.112 cm(-1). Spectral regions measured include the vibrational bands: v(1) (similar to 3552 cm(-1)), v(2) (similar to 1710 cm(-1)), v(3), v(4) (similar to 1320 cm(-1)), and v(5), 2v(9) (similar to 890 cm(-1)) and regions of weaker absorption between 820 and 5300 cm(-1). We observe expected changes in the distribution of rovibrational intensities with temperature, but to the accuracy of our measurements, cross-sections integrated over entire vibrational bands are independent of temperature. (C) 2003 Elsevier Ltd. All rights reserved.