A multispectrum analysis of the ν1 band of H12C14N: Part I. Intensities, self-broadening and self-shift coefficients

Abstract The infrared spectrum of HCN in the region between 3150 and 3450 cm −1 has been recorded at 0.005 and 0.008 cm −1 resolution using two different Fourier transform spectrometers, the McMath–Pierce Fourier transform spectrometer located at the National Solar Observatory (on Kitt Peak) and the Bruker-120HR Fourier transform spectrometer situated at the Pacific Northwest National Laboratory at Richland, Washington. Room temperature measurements were made of positions, absolute intensities, self-broadening and self-shift coefficients for individual lines belonging to the HCN ν1 band centered near 3311 cm −1 . These are to our knowledge the first extensive set of self-broadening and self shift measurements in the band. In addition, intensities, self-broadening and self-shift coefficients for several lines of the ν1+ν21−ν21 hot band and several intensities for lines in the H13C14N and H12C15N isotopomers were also determined. A multispectrum nonlinear least-squares fitting algorithm was used to fit the entire spectral region covering the 3200– 3400 cm −1 region of up to 27 spectra simultaneously. The measured line intensities in the ν1 band were further analyzed to derive the vibrational band intensity and the Herman–Wallis coefficients. Differences in line intensities between 5 and 10% are found with respect to present measurements and the values given in the HITRAN database for m values beyond 25 in the P branch and 5 in the R branch.