From the theory of the diffuse scattering of x-rays by single crystals it appears that the ratio of the intensity of the incoherent to that of the total scattering at a given angle should be a function of the temperature. Accordingly x-rays of wave-length 0.40A were scattered from sylvine at temperatures of 300°K and 90°K. Aluminum was transferred from the primary to the scattered beam and from the observed change of absorption coefficient of the x-rays the above ratio was calculated. It was found that this ratio increased as the temperature decreased.

• Received 10 March 1932

DOI:https://doi.org/10.1103/PhysRev.40.329