Molecular Optical Spectroscopy with Supersonic Beams and Jets.

摘要

This account is a description of a recent technique which is directed toward overcoming two difficulties which arise when one wishes to study the high resolution spectra of molecules. The first of these is the necessity of obtaining a sample of the molecules at a temperature which is low enough to prevent thermal dissociation and which contains population of only as many rotational and vibrational levels of the molecular system as can be separately assigned in the spectrum. The second difficulty lies in finding a medium which will support the molecular system at this low temperature without introducing undesirable changes and complications in the spectrum. A desirable spectroscopic sample would be an ensemble of molecules, all in a particular and well-defined quantum state (usually the lowest energy allowed state) traveling in free space with a narrow velocity distribution, and at a sufficiently low density so that intermolecular interactions are unimportant. The purpose of this account is to trace the progress of research in the application of supersonic beams and jets toward the solution of a number of problems in molecular optical spectroscopy and to illustrate the promise such experiments hold for future work.