RESONANT RAMAN SCATTERING BACKGROUNG IN XRF SPECTRA OF BINARY SAMPLES

HÉCTOR SÁNCHEZ; MARÍA VALENTINUZZI; JUAN JOSÉ LEANI

Puebla

Seminario; 12° Latin-American Seminary of X-Ray Techniques (SARX); 2010

Sociedad Mexicana de Fisica

ABSTRACTX-ray fluorescence spectra present singular characteristics produced by the differentscattering processes. When atoms are irradiated with incident energy lower and close toan absorption edge, scattering peaks appear due to an inelastic process known asresonant Raman scattering. In this work we present theoretical calculations of theresonant Raman scattering contributions to the background of X-ray fluorescencespectra. In order to perform the calculations the Shiraiwa and Fujino's model was usedto calculate characteristic intensities and scattering interactions. This model makescertain assumptions and approximations to achieve the calculations, especially in thecase of the geometrical conditions and the incident and take-off beams. The calculationsshow that the Raman scattering background is significant under the fluorescent peak,affects the symmetry of the peaks and, depending on the concentrations, overcomes theenhancements contributions (secondary fluorescence).The model proposed here allows analyzing the different sources of background, whichcontribute to a better understanding of the physical processes involved in the differenttechniques of XRF analysis.