Transition Dipole Moments for the Vibrational Fundamentals of HNC Determined from the Herman–Wallis Effect

Abstract

The ν1and ν3fundamental bands of HNC are recorded with a Fourier transform infrared spectrometer with a resolution of 0.008 cm−1. Hydrogen isocyanide is generated in situ by dc discharge in a mixture of CH3CN (∼40 mTorr), H2(∼160 mTorr), and Ar (∼160 mTorr). The transition dipole moments for these fundamental bands are determined from the analysis of the Herman–Wallis effect, and they are compared withab initiocalculated values. It is found that theab initiovalues for the ν1and ν3bands are about 50 and 30% larger, respectively. The transition dipole moments determined are to be of use for determination of the abundance of HNC in reaction systems such as the dissociative recombination reaction of HCNH+with electrons.