Knowledge Bank

Hydrogen peroxide is the simplest molecule that can execute torsional motion, and as a light asymmetric rotor has substantial centrifugal distortion contributions to its rotational-torsional spectrum. The spectrum and analysis of HOOH include the n = 0 and n = 1, $\tau =1,2$ and $\tau =3,4$ torsional states. In addition, transitions between the n=0 torsional sublevels in $V3$ and $V6$ have been measured. The ground state analysis is a combined fit that includes recent in frared $data1,2$ with the microwave data. The model uses the Watson A-reduced Hamiltonian and includes a fermi resonance interaction between the torsional states. Both sets of data are fit to their respective uncertainties. The results of this analysis will be presented, along with the assignments for the $V3$ and $V6$ transitions.