Advances in X-ray Analysis

X-ray diffraction as a method of qualitative analysis for crystal- line phases has been long accepted, and has had constant improvement in method and equipment. It has also been made more useful by the growth and improvement of the data collection available as reference standards. In recent years some attempts have been made to use the method to a greater extent by furnishing results on a quantitative basis. This has proved to be difficult because of the problem of comparing the relative intensities of the diffraction peaks from one phase to another. This year the initial session of invited papers focuses primarily on this problem. The subject is approached both by the use of internal comparison standards and by calculation of intensities. In addition, the identification of crystalline phases by X-ray diffraction of single crystals is discussed in an invited paper. This method, with its advantages of the use of very small samples, is becoming increasingly feasible because of the development of simple equipment and the avail- ability of a growing data bank. Other X-ray diffraction developments discussed at the Conference include stress analysis, use of computers for searching the JCPDS powder diffraction file, texture analysis, and applications to specific fields. Spectroscopy topics covered at the conference included a discussion of methods of concentration of materials for fluorescence analysis, soft X-ray spectra, and equipment for fluorescence analysis.