X-ray fluorescence: From the discovery of Roentgen rays to Tertian identities

The X ray fluorescence radiation was observed from the year after the discovery of X-rays by Rontgen. But, it is from the work of Laue (1913) that X ray fluorescence spectrometry expanded rapidly. Previous studies (Sagnac, Barkla, ...) was thus confirmed by Moseley that established the relation between X spectra lines and Mendeleieff elements classification table. It was the begining of qualitative analysis. From the 1945-1955 period, and with the use of goniometers, the method was largely employed in industrial analyses and was supported by the improvment of the apparatus as well as the developpment of new theories on X-ray fluorescence emission. These research have led to matrix effect correction algorithms including inter-elements influence coefficients. In 1977, Tertian based a correlation between these coefficients and the fondamental equations of fluorescence intensities. These works known as Tertian Indentities were applied to the quantitative analysis (Broil-Tertian) and more recently to developp semi-quantitative method analysis.