Broad vibrational overtone linewidths in the 7νOH band of rotationally selected NH2OH

Abstract
Infrared–optical double‐resonance spectroscopy of the 7νOH vibrational overtone level of NH2OH reveals 14 cm1 wide spectral features. The product state distribution of the OH fragment subsequent to overtone excitation indicates that the 7νOH level of NH2OH is ∼128 cm1 above the N–O bond dissociation energy. Comparison to HOOH overtone spectra at a similar excess energy suggests that the broad NH2OH linewidths result from vibrational state mixing at the 7νOH level and not from inhomogeneous structure or lifetime broadening of the dissociating molecules. The observation of 14 cm1 overtone linewidths for a molecule the size of NH2OH suggests that the broad vibrational overtone transition linewidths in larger polyatomics may contain a substantial homogeneous component.