Integrated intensities for some infrared absorption bands of HCN

Abstract

The integrated intensities of several vibrational bands of HCN have been measured using a Fourier transform infrared spectrometer. The experiments yield the following values for the integrated intensities in cm^–2 atm^–1 at 298 K: ν₃, 255 ± 11; 2ν₂, 34.7 ± 0.9; ν₂+ν₃, 4.8 ± 0.4; ν₁+ν₂, 2.9 ± 0.3; ν₃–ν₂, 0.51 ± 0.04. The spectra also reveal that much of the weak absorption between 2200 and 2000 cm^–1 is due to the 3ν₂ band and to a band of the (HCN)₂ dimer. The imegrated intensity of the ν₁ band is estimated to be only ca. 0.1 cm^–2 atm^–1.