X-RAY-FLUORESCENCE ANALYSIS OF RARE-EARTH ATOMS IN MATERIALS BY USE OF ULTRASHORT WAVELENGTH X-RAYS

A new technique of X-ray fluorescence analysis using ultrashort-wavele ngth X-rays was tested to obtain the K-series of spectra for rare-eart h elements in two different kinds of materials, i.e. powder samples of rare-earth oxides and single crystals of rare-earth hexaborides. This technique utilizes a solid-state detector and multichannel pulse-heig ht analyzer, and satisfies the requirements for quantitative identific ation in samples containing heavy elements. This technique was applied to determine the composition of the mixed compound La1-xCexB6 (z = 0. 25, 0.50 and 0.75). There is good agreement, within the limits of expe rimental error, between the values thus obtained and the nominal value s.