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K␤ x-ray spectra of metallic vanadium and its compounds ͑V 2 O 3 , VO 2 , V 2 O 5 , VC, VN, VCl 2 , NH 4 VO 3 , and VOSO 4 ϫ 5H 2 O͒ induced in thick targets by 3 MeV proton beams were measured by using wavelength dispersive ͑WD͒ x-ray spectrometer. In addition to the main K␤ 1,3 x-ray line, "satellites" or second order contributions like K␤Ј, K␤Љ, K␤ٞ, and K␤ 2,5 were clearly resolved. Intensities and positions of these lines relative to the K␤ 1,3 x-ray line have been extracted by fitting the spectra and corrected for x-ray sample self-absorption. The influence of the oxidation states and vanadium-ligand bond distances in studied compounds on relative intensities and positions of K␤Љ, K␤ 2,5 , and ͑K␤Љ + K␤ 2,5 ͒ x-ray lines ͑relative to K␤ 1,3 + K␤Ј͒ has been studied and discussed. The obtained results indicate that the strength of the K␤Љ and K␤ 2,5 transition probability per vanadium-ligand pair decreases exponentially with increasing vanadium-ligand distance, in agreement with the observation reported by Bergman et al. for K␤Љ relative intensity in a number of Mn oxide compounds ͓U.

Large database of high resolution Kb X-ray emission spectra of selected 3d metal (Ti, V, Cr, Mn) compounds obtained after excitation by 2 and 3 MeV proton beams have been built. Analysis of (relative) positions and intensities of Kb 00 and Kb 2,5 X-ray contributions as a function of chemical and structural properties of analyzed 3d metal compounds have been performed. Two independent experiments employing wavelength dispersive spectrometers with different experimental resolutions (8.1 eV versus 2.8 eV for the case of Cr Kb 1,3 line FWHM) were performed in order to exclude any possible effect of the experimental resolution on the extracted values. A simple parametrization of Kb 00 and Kb 2,5 X-rays' relative positions and intensities over the range of 3d metal compounds with various oxidation states, a wide range of metal-ligand bond lengths, and selected 3d metals, was performed. Results of our parametrization were compared critically with other experimental and theoretical values available in the literature. The parametrization obtained in this work could be used for chemical and structural speciation of 3d metal compounds and for improved interpretation of K X-ray spectra of 3d transition metal compounds measured by solid state detectors.

Nowadays quantitative analysis in energy dispersive X-ray Emission Spectroscopy is usually performed by the "fundamental parameter approach". Such an approach generally relies upon a good knowledge of fundamental physical parameters. As a rule none of the algorithms in use by laboratories performing routine analysis account for possible chemical effects on X-ray intensity ratios or energies. Here we tested the possible influence of such practice on reliability in the routine analysis of thick pellet samples containing transition metal compounds. A number of samples were prepared by mixing various proportions of MnO 2 , KMnO 4 , and Co 3 O 4 (sets A-B) or Cr 2 O 3 , K 2 Cr 2 O 7 , and Fe 2 O 3 (C-D). The samples were irradiated by 2 MeV proton beams and proton induced X-ray emission spectra were analyzed by a "fundamental parameter" approach using the GUPIXWIN code. The main interest has been to test the possibility of false Fe detection in the presence of large Mn and Co peaks (sets A-B) and/or Mn in the presence of large Cr and Fe peaks (sets C-D). The results of the analyses indicate false hits of Fe (sets A-B), and larger reported Mn concentrations than expected (sets C-D). However, in all the cases the reported concentrations for Fe or Mn are in between the limits of detection and quantitation. The influence of surface roughness and other effects have been discussed.