Quantitation Of The Production Cross-Section And Transition Probabilities Of The L And M X-Ray Series In The Au(0) And Au(3+) Atomic Environments Using Total-Reflection X-Ray Fluorescence

This work presents the quantitation of the effects that different chemical environments induced in the transition probabilities of their L and M series spectra working in the particular geometrical and analytical conditions imposed by the Total-reflection X-Ray Fluorescence (TXRF) spectrometry. The evaluated chemical environments were metallic Au(0) and chloride Au(3+) phases, with different oxidation states and different crystal field surroundings. Lines Ll, L alpha, Lri, L beta, L gamma and the overlapped M alpha and M beta, named as M alpha beta, were evaluated. Transition probabilities and production cross-section ratios were calculated for both gold environments. The absolute transition probabilities were evaluated as the intensity of each line versus the sum of the set of intensities investigated, i.e. Au L and M lines. Achieved results show significant differences between both gold chemical states and environments higher than uncertainties. TXRF has proven to be sensitive to the transition probabilities induced by different atomic environments. Intensity variations with decrements of -7.3% for L beta line and increments of 96% for M alpha beta lines were measured. In parallel, the same phenomenon observed for gold has been observed qualitatively and for the first time by TXRF in three different phases of lead, metallic Pb(0), nitrate Pb (2+) and sulfide Pb(2+). The achieved results corroborate the ability of TXRF to investigate the, different oxidation states, differents crystalline phases, different environments and in a general way, the different chemical surrounding effect. Finally, the existence of a possible enhancement effect in the Au M alpha beta line due to a secondary excitation by the presence of Cl K alpha secondary excitation was also checked. Results indicate that the observed change of M alpha beta intensities between metallic gold and gold chloride are not due to the Cl K alpha enhancement effect.