Very High Precision X-ray Diffraction

VERY high precision has been obtained in the measurement of X-ray diffraction angles, such that if translated into terms of changes in the crystal lattice constant, a precision of 1 part in 10,000,000 can be attained. All indications are that the limit of sensitivity can be extended even further. Fig. 1 shows the application of the method to measurements of the coefficient of thermal expansion of magnesium oxide over a temperature range of 1° C, and gives a clear idea of the sensitivity that is at present being obtained.