Further Remarks on the Techniques of Molecular Spectroscopy

Abstract

In molecular spectroscopy, the energy levels of molecules which are connected by absorption, by radiationless processes, or by the emission of radiation are investigated (Sects. 15.1 through 15.3). The method of laser spectroscopy of cold molecules in a supersonic molecular beam has been the source of major advances in molecular spectroscopy (Sect. 15.4). With this technique, one can also study short-lived and weakly bound complexes and clusters; the new modification of carbon, the Fullerenes, were discovered in this way (Sect. 15.4). An important experimental tool is the tunable dye laser (Sect. 15.5). Employing a combination of these modern methods, it has proved possible to resolve the rotational structure of the vibronic bands of large molecules with two-photon absorption or excitation spectroscopy (Sect. 15.6). Using pulsed lasers, dynamic processes within and on molecules down to the femtosecond range can be investigated (Sect. 15.7).