Electronic Spectra of Polyatomic Molecules—A Brief Survey

A brief discussion is given of the early contributions of R. S. Mulliken and his school to the study of the electronic spectra of polyatomic molecules. An up-to-date summary of the polyatomic molecules and free radicals for which high-resolution studies of their band spectra have been carried out is included. Some points of likely interest to the theoretical worker are discussed, including the Renner effect in AH2 and BAC molecules, predissociation in HAB molecules, and some recent experimental results on the allyl and vinoxy radicals.