A simple modification of a conventional excitation unit for the Raman effect is described that allows study of the effect in liquids at temperatures down to about -150°C. The chief feature of the arrangement is a Dewar-jacketed sleeve that fits around the Raman tube and enables the cooling of the tube by a flow of cold nitrogen gas. By adjustment of the temperature of the gas and its rate of flow, easy and precise control of the temperature of the Raman tube can be obtained. It is also possible to use elevated temperatures (up to +150°C) by heating the nitrogen. The advantages of the system are its simplicity, ease of operation, rapidity of change from low temperature to normal operation, and vice-versa, and the same intensity of illumination as that afforded by room-temperature operation.
R. C. LORD and E. NIELSEN, "Apparatus for Low Temperature Study of the Raman Effect," J. Opt. Soc. Am. 40, 655-655 (1950)