FAMILY OF ALPHA-COEFFICIENTS IN X-RAY-FLUORESCENCE ANALYSIS

The demand for comprehensive analysis of materials by XRF using automated instrumentation has led to increasing use of the coefficient approach for dealing with the ever‐present interelement effect. A survey of the literature shows that this has often led to a multiplicity of families of calibration curves being replaced by a multiplicity of tables of correction coefficients. A practical approach is outlined which facilitates the recognition of (a) the alpha subset of influence coefficients, and (b) three related subsets of alpha coefficients – basic, modified and hybrid. This mobility of alpha coefficients (alloys, oxides, fusions, solutions) coupled to their adaptability (geometry, primary radiation) and accessibility (theoretical, experimental) has wide implications. It permits a consolidated view of the influence coefficients, and comparison of the sign, magnitude and pattern of basic alphas so as to establish if and when there is consensus. The confirmed alpha coefficients thus obtained can then be transferred with confidence to suit specific operating conditions and methods. Examples are given using data that have appeared in XRF literature. Copyright © 1979 Heyden & Son Ltd.