A Relation between Raman Spectra and Ultra-Violet Absorption

Abstract

IT is well known that the Raman frequencies are identified with vibration frequencies of the molecule, and this is corroborated by the agreement already found between Raman lines and absorption bands in the infra-red. It is to be anticipated, however, that a polyatomic organic molecule with its several frequencies of vibration would give a rather complicated absorption spectrum, so that the dispersion of the spectroscope in the infra-red is often insufficient for their resolution. The result is therefore a super-position of bands on a continuous background, the maxima of which may correspond to average values between two or more bands. In fact, the agreement between Raman spectra and infra-red absorption is in many cases not quite satisfying.