Infrared Spectroscopy of Triatomics for Space Observation || Clathrate Nano-Cages

摘要： Determining the presence and evolution of molecular species and their physicochemical environment in astrophysical media makes high-resolution infrared spectroscopy a powerful investigative tool that would provide a great deal of information on how these molecules behave in their environments. In this chapter, we describe the theoretical models developed to analyze the absorption spectra of a triatomic molecule trapped in a clathrate nano-cage at very low temperatures. The Lakhlifi–Dahoo extended inclusion model allows the determination of the trapping site (cage structure type), position and movements of the molecule in its site. Frequency shifts due to the solid environment can be interpreted using an atom–atom potential model to describe the interaction between the clathrate matrix and the trapped molecule. Moreover, this inclusion model makes it possible to determine the IR spectra and the couplings with the atoms or molecules forming the nano-cage.