Raman spectrum of deuterium: II. Intensity and polarisation characters

Abstract

Measurements have been made of the intensity and polarisation of the lines in the Raman spectrum of deuterium. The results, when compared with those calculated from the theory of rotational Raman scattering due to Manneback, show satisfactory agreement. The vibration Raman line in deuterium is found to exhibit a depolarisation factor of 0.18 and an intensity of about one-tenth the aggregate intensity of the rotational scattering. From-this result it is estimated that the intensity of the vibration line is about 1/300 of that of the Rayleigh line. This is an unusually large ratio for gases and has hitherto been found only in hydrogen. Further work in relation to the fine structure of the vibration line and the inter-comparison of the P, Q and R branches is in progress and will form the subject-matter of the next paper in this series.