Habilitation à diriger des recherches of Manuel Goubet

 Habilitation à diriger des recherches of Manuel Goubet Microwave and infrared spectroscopy of hydrogen bond complexes Abstract : This thesis summarizes part of my work since my PhD thesis with a focus on the spectroscopy of hydrogen bond complexes. The structure and dynamics of the hydrogen bond are studied by microwave and/or infrared spectroscopy of samples observed in jet-cooled conditions, with the support of quantum chemistry calculations. The objectives are both fundamental, oriented towards the understanding of this peculiar sort of bond halfway between the ionic bond and the long-range interaction known as van der Waals, and for the environmental sciences, oriented toward the study at the molecular level of the interactions of volatile organic compounds with their environment, leading or not to the formation of secondary organic aerosols. Three main families of hydrogen bonds pose different questions and often require specific treatments: intramolecular bonding, which influences the intrinsic properties of flexible molecules; hetero-complexes, which influence condensation or take part of chemical reactions; dimerization, which is the first step in agglomeration processes. In parallel with this main activity, the recording and modeling of the spectrum of aromatic compounds in the microwave and infrared domains are also addressed. These studies deliver lines positions and intensities to spectroscopic databases, making their signals available for their identification or not in the spectral recordings of stellar sources carried out by radio-astronomical observatories. In addition, from a fundamental point of view, the characterization of the physico chemical properties of aromaticity contributes to knowledge on this major family of chemical compounds. A new project has recently started, focusing on the detection of explosives taggants in a context where the fight against terrorism has become a major societal issue. The objectives are, on the one hand, to develop a detection system capable of identifying traces of explosives in order to replace canine detection and, on the other hand, to build a database of spectral signals from those explosives taggants. Finally, the instrumental developments as well as the implementation of a new chirped pulse spectrometer, opening up the way to new research opportunities, are discussed.