ON THE SHAPE AND WIDTH OF THE MAIN LINES OF X-RAY K EMISSION OF THE 3 d AND 4 d ELEMENTS

Abstract

This paper deals with the changes of the line shape (in particular width and asymmetry) occuring with the main emission lines of the K series (Kα1.2 and Kβ1.3). The measuring results gained so far are reviewed and analyzed. A first report is given on the changes of the shape and width of the Kα1.2 doublet of 42Mo influenced by the chemical bond. As a relevant kind of representation of such changes the so-called line-cross section is introduced. For the Kα1 lines of the 3 d elements an attempt is made to give a quantitative relation to the number of unpaired electrons. Most successful for the interpretation of these effects proved the application of the theory of the multiplet structure on X-ray spectra. An analysis of the calculations basing on this procedure reveals the necessity of a distinct limiting of the approximation stages used. This work treats notably the mode of the coupling of the moments, in particular the jj-coupling. For this purpose, the spin-orbit coupling parameters ζ3d and ζ4d, resp., for 3 d and 4 d elements were determined by extrapolation. We notice that the pure jj-coupling yields for the lines of the 3 d elements a too small broadening and for those of the 4d elements a too large broadening and that for the Kζ1,2 doublet of the 3 d elements (in contrast to that of the 4 d elements) an additional consideration of the electrostatic interaction (intermediate coupling) improves the agreement with experiment.