I AM INTERESTED IN THE SPECTROSCOPIC CHARACTERIZATION OF SMALL, OFTEN VERY REACTIVE MOLECULES, PARTICULARLY THOSE OF ATMOSPHERIC OR ASTROPHYSICAL AND ASTROCHEMICAL INTEREST. Spectroscopic Techniques The spectroscopic techniques include rotational as well as low and high resolution infrared spectroscopy. And as a chemist, I am not afraid of synthesizing these molecules on a preparative scale or in situ. Throughout my scientific career, force field and quantum chemical calculations (ab initio, DFT) played an important role. Some more detail are in the following sections. Initially, I have studied mathematics and chemistry to become a teacher. During universitiy years, the emphasis was on mathematics, while it was on chemistry during the practical period in school.