Use of Κβ/Κα Intensity Ratios for the Study of Annealing Processes in ⁵¹Cr-doped Solids

Abstract

Kß/Ka X ray intensity ratios from the electron capture decay of 51 Cr in S1 Cr (IH)-doped oxyanion salts were determined before and after annealing treatments. The observed change in the ratio is consistent with the overall process: 51 Cr (III) 51 Cr (VI), also inferred from solution analysis of the annealed samples. However, for most samples, the fraction of SI Cr (VI) calculated from the "in situ" analysis was less than that indicated by the solution analysis. No change in the ratio was seen with changes in the relative amounts of 51 Cr (III)-monomer and 51 Cr(III)-dimer + polymer. These observations suggest that the Kß/Ka "in situ" technique may be useful in following the overall process although it may not be sufficiently sensitive to distinguish the 51 Cr solid state precursor species.

Influence of chemical environment on the analysis of X-ray spectra of thick pellet samples containing 3d transition metal compounds

“…The gure suggests that this ratio is larger for set D, corresponding to the mixed samples of K 2 Cr 2 O 7 + Fe 2 O 3 . This would be in line with the ndings of Collins et al 11 that experimental thin target Kb/Ka intensity Fig. 6 The ratios of the reported and expected Mn concentrations for samples of sets C-D as a function of Cr concentrations.…”

“…Large variations exist between reported intensity ratios, probably inuenced by the fact that most of the data have been obtained on thick targets. Only few experiments have been performed on thin targets, one of them by Collins et al, 11 who reported an average Kb/Ka value of 0.1316 for Cr(0), a value of 0.1382 for Cr(III) and 0.1467 for Cr(VI) in measured thin-layer chromium containing samples, which they claimed to be sufficient to distinguish the several oxidation states from the related X-ray spectra. Brunner et al 12 reported relative Kb/Ka intensity ratios between thin Cr metallic and K 2 Cr 2 O 7 samples to be 0.977 AE 0.007.…”

Intensity Ratio of Kβ/Kα in Selected Elements from Mg to Cu, and the Chemical Effects of Cr Kα1,2 Diagram Lines and Cr Kβ/Kα Intensity Ratio in Cr Compounds

“…Using ionization by electron bombardment, Hölzer et al [ 9 ] found that the contribution of this shake process was present throughout the diagram lines. On the other hand, several experiments have been performed to investigate the chemical effect on the intensity ratios for elements [ 10 , 11 , 12 ]. Brunner et al [ 13 ], who used protons as the ionization method, explained their experimental results by a contraction of orbitals due to the charge delocalization of the valence electrons.…”