X-ray Diffraction Automation and its Use in Clay Mineralogy

Stanley B. McCaleb
Sun Oil Company, Richardson, Texas

Abstract: The standard Philips X-ray Diffraction equipment has been fully automated for continuous unmonitored operation. Modifications of the equipment include a sample-changing device, goniometer-driven divergence slits, pulse motor drive with eight-speed option, selective scan speed as a function of hkl intensity, range change device, and electronic programming of the complete operation. In addition, simultaneous readout on the Brown Recorder strip chart and magnetic tape provide records for visual and computer processing.

Computer programs have been developed for the processing of the digital output that is in the form of cumulative pulse counts for the angular position and the intensity of the reflection. These data are converted to hkl spacings in angstroms and intensities after removal of the background count. An identification program has been developed that identifies the minerals and prints out the spacings and intensities used for the identification. Solvation and heat treatment data are utilized to aid in the identification of the clay minerals.

Selected data from sediments are used to illustrate the output of the automated instrument and the increased resolution and speed of the equipment.

Clays and Clay Minerals; 1964 v. 13; no. 1; p. 123-130; DOI: 10.1346/CCMN.1964.0130114
© 1964, The Clay Minerals Society
Clay Minerals Society (www.clays.org)