An X-ray diffraction study of liquid mercury between 50C and 150C

Interference functions from liquid mercury have been obtained at 50, 100 and 150 degrees C, using a specially designed X-ray diffractometer. The important feature of the results is the rapid change of first peak height with temperature. By matching the observed interference functions to those from a hard sphere model it is found that the equivalent packing density of the liquid changes from 0.42 at 50 degrees C to 0.32 at 150 degrees C. From these values of the packing density the compressibility has been calculated at each temperature and all are higher than the published experimental values. It is concluded that there may be an increase in the inter-ionic repulsive force as the temperature increases.