Knowledge Bank

Using high resolution Fourier transform spectra $(\sim 0.002cm-1)$ recorded at IROE and at Giessen, it was possible to measure 2072 line intensities from the torsion-rotation spectrum of $H2O2$ in the $25-400cm-1$ spectral region. These intensities were introduced in a least squares fit calculations to get the expansion of the transition moment operator of the torsion-rotation band of $H2O2$. Finally a synthetic spectrum of the far infrared absorption of $H2O2$ was generated, using for the line intensities the dipole moment expansion determined in this work and for the line positions the parameters from $Camy-Peyretetal(1)$: in addition to the the vibration-rotation resonances involving the ground state and the $\nu 3=1$ vibrational state, the $model(1,2)$ used to calculate the positions and intensities takes into account the torsional effect i.e. the torsional dependence of the dipole moment and the $(\Delta \top =\pm 1,\Delta Ka=\pm 2)$ torsion-rotation resonances within the ground vibrational state, together with the ``staggering'' effect which is due to the tunnelling through the cis-barrier. Financial support from the European Community under contract EV5V-CT92-0076 is gratefully acknowledged.