JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY, vol.278, no.1, pp.89-96, 2008 (SCI-Expanded)
In this study, the chemical effects on sigma(Ki) (i = alpha, beta), sigma(L alpha) cross sections, K-beta/K-alpha X-ray intensity ratios and vacancy transfer probabilities from K to L (eta (KL)) for pure Nb and Nb compounds were investigated. The samples were excited by 59.5 keV gamma-rays from Am-241 and 5.96 keV photon energy from a Fe-55 annular radioactive sources. K and L X-rays emitted by samples were counted by an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. While it was observed that the chemical bonding had an effect on the sigma(K beta), sigma(L alpha) cross sections and K-beta/K-alpha X-ray intensity ratios for compounds, it was almost negligible for sigma(K alpha) cross section because K-alpha transitions (2P(3/2,1/2)-> 1S(1/2)) occurred in inner shells. It is well known that interactions between central element atom and ligands come into existence in valence state, so outer energy levels are sensitive to the chemical environment. The experimental values of sigma(K alpha) cross section and eta (KL) are in good agreement with theoretically calculated and other experimental values of pure niobium, but the experimental values of the sigma(K beta), sigma(L alpha) cross sections and K-beta/K-alpha X-ray intensity ratios have differences for some compounds because valence electrons have different bond distances and binding energies in different compounds.