15min:
THE THZ SPECTRUM OF GLYCOLALDEHYDE.

MANUEL GOUBET, THERESE R. HUET, IMANE HAYKAL, LAURENT MARGULES, Laboratoire PhLAM, UMR8523 CNRS-Universite Lille 1, F-59655 Villeneuve d'Ascq Cedex, France; OLIVIER PIRALI, PASCALE ROY, Ligne AILES - Synchrotron SOLEIL, L'Orme des Merisiers Saint Aubin, F-91192 Gif-sur-Yvette, France.

The vibration-rotation spectrum of the nu1-0, nu2-0 and nu3-0 bands of glycolaldehyde was recorded up to 12 THz, using the far-infrared beamline AILES at the synchrotron SOLEIL and a Fourier transform spectrometer coupled to a multipass cell. More than eight thousands lines were assigned, revealing the rotation structure up to J=80, Ka=38 for the ground state. The THz data were fitted simultaneously with pure rotational transitions of better accuracy observed in the microwave (1), in the millimeter-wave (2) and in the sub-millimeter-wave (3) range. In addition new data were recorded at Lille in the 150-300 GHz and 750-950 GHz range. The THz lines and the microwave - (sub)-millimeterwave lines are reproduced with a standard deviation of 2 10-4 cm-1 and 40 KHz, respectively.

Glycolaldehyde has been identified toward the galactic center (4). The vibrational state partition function can be re-evaluated according to the bands origins associated with nu1, nu2, and nu3, which are observed experimentally for the first time.

This work is supported by the Programme National de Physico-Chimie du Milieu Interstellaire (PCMI-CNRS) and by the contract ANR-08-BLAN-0054.

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