Fourier transform spectroscopy of the ν3 band of the N3 radical

Abstract
We have analyzed the ν3 antisymmetric stretching fundamental of the N3 radical. Azide radicals N3 were generated in a multipass cell by the reaction of Cl atoms and HN3 and detected in absorption using a Fourier transform spectrometer. Improved constants for the 000 vibrational level of X̃ 2Πg are reported along with observations of the 001 level. The frequency of the ν3 fundamental at 1645 cm−1 was found to be somewhat lower than expected.