A new approach to X-ray absorption analysis is presented in this paper. The equation log (I2/I1) = KWA + KB is used, from which the weight fraction WA of a given element can be calculated in various solvents when only a calibration curve from one solvent and the absorption of the new solvent at two wavelengths (λ1 and λ2) are known.

This treatment uses the absorption at two wavelengths, one on each side of an absorption edge of the element under study. The desired wavelengths can be conveniently obtained from the Kα and Kβ radiation of an element with an atomic number just higher than the element under study. An easy way to accomplish this is to use the desired target element as the sample in an X-ray spectrometer. The Kα and Kβ radiations are then resolved with an appropriate analyzing crystal, and the absorption measurements are made consecutively.

The advantages of this approach are twofold. First, it is only necessary to do a full calibration curve in one solvent; calibration in other solvents can be calculated with only a knowledge of the absorption of that pure solvent at the wavelengths used, which can. either be determined experimentally or calculated. Secondly, the required experimental data can be collected very conveniently in an X-ray spectrometer.