15min:

S. KLEE, M. WINNEWISSER, Justus Liebig Universit\Hat, , Physikalisch-Chemisches Institut Heinrich-Buff-Ring 58, D-35392 Gieß en, Deutschland; A. PERRIN, J.-M. FLAUD, Laboratoire de Photophysique Moléculaire, CNRS, Université Paris Sud, Campus d'Orsay, Bat 210, 91405 Orsay Cedex, France.

The purpose of this work was to obtain reliable absolute intensities for the ₆ band of H₂O₂. This work was undertaken because strong discrepancies exist between the different ₆ band intensities which are presently available in the

literature .

The method which was used in the present work is to use Fourier transform spectra of H₂O₂ recorded at Giessen in a spectral range (370-1270cm^-1) which covers both the R-branch of the torsion-rotation band at low wavenumber and the P-branch of the ₆ band at high wavenumber. \begin itemize em From the low wavenumber data, the partial pressure of H₂O₂ present in the cell during the recording of the spectra was determined by calibrating the observed absorptions in the torsion-rotation band with intensities computed by using the permanent H₂O₂ dipole moment measured by Stark effect . em In the high frequency range, this value of the partial pressure of H₂O₂ was used to measure absolute line intensities in the ₆ band. \end itemize Finally, the line intensities in the ₆ band were fitted using the theoretical methods described in detail in our previous works ^a,c.