Multimode calculations of rovibrational energies and dipole transition intensities for polyatomic molecules with torsional motion: application to H2O2

We report rigorous calculations of rovibrational energies and dipole transition intensities for hydrogen peroxide using a new version of MULTIMODE as applied to molecules with torsional (reaction path) motion. The key features which permit such calculations for moderately sized polyatomic molecules of this general type are briefly described. A previous, accurate potential energy surface and a new high-level ab initio dipole moment surface are employed in these calculations. Detailed comparisons are made with high-resolution experimental spectral intensities from the HITRAN database.