The High-Resolution Infrared Spectrum of Nitryl Chloride: Rotational Analysis of the 35CINO2 ν4 Band Around 6 μm

Nitryl chloride (ClNO[sub 2]) is involved in heterogeneous stratospheric chemistry by the reaction of HCl with N[sub 2]O[sub 5] on polar stratospheric cloud particles. The present work reports the first high-resolution infrared absorption spectra of nitryl chloride. The authors have recorded two infrared absorption spectra of ClNO[sub 2] at room temperature between 450 and 2,450 cm[sup [minus]1] with a stepping-mode Fourier transform spectrometer at 0.0028 cm[sup [minus]1] nonapodized resolution. The spectrum shows rich, well-resolved rotational structure in the [nu][sub 6] (652 cm[sup [minus]1]), [nu][sub 2] (792 cm[sup [minus]1]), [nu][sub 1] (1,268 cm[sup [minus]1]), 2[nu][sub 6] (1,318 cm[sup [minus]1]), and [nu][sub 4] (1,684 cm[sup [minus]1]) bands. They have carried out a rotational analysis of the [nu][sub 4] band of [sup 35]ClNO[sub 2] around 1,684 cm[sup [minus]1], leading to the assignment of 1,691 b-type transitions. The authors have determined new rotational constants for the ground state, and the rotational constants for the [nu][sub 4] = 1 vibrational state.