Effect of OH internal torsion on the OH-stretching spectrum of cis,cis-HOONO.

We show that a simple two-dimensional vibrational model can explain most of the features observed in the first and second OH-stretching overtone region of the room temperature cis,cis-HOONO spectrum. The model uses ab initio calculated parameters and includes the OH-stretching mode coupled to the internal torsion of the OH group.