IFEG   20353
INSTITUTO DE FISICA ENRIQUE GAVIOLA
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
X ray resonant inelastic scattering on pure samples and oxides
Autor/es:
MARÍA CECILIA VALENTINUZZI; HÉCTOR JORGE SÁNCHEZ; JOSÉ ABRAHAM; CARLOS PÉREZ
Lugar:
Campinas, Brasil
Reunión:
Congreso; Reunión Anual de Usuarios de LNLS (RAU 2008); 2008
Institución organizadora:
Laboratorio Nacional de Luz Sincrotrón
Resumen:
By means of X ray spectroscopy it is possible to characterize materials since when X rays interact with atoms different processes take place such as the photoelectric absorption, the Rayleigh scattering and the Compton scattering, leading to spectra with characteristic lines that allow to identify the components of the target and it is also possible to perform a quantification. But there are other processes that can alter the spectra obtained with X ray fluorescence, producing peaks that interfere with the fluorescent one causing a problem that has not been studied in detail so far. These processes are inelastic scattering processes, such as the resonant Raman effect with an enhancement of the resonant behavior as the incident energy approaches the absorption edge. In this work we present a comparison of the inelastic resonant scattering (Raman effect) on pure samples and oxides in order to study if the oxidation state of the sample can interfere with the scattering process. The measurements were carried out in XRF station of the D09B-XRF beamline at Brazilian synchrotron facility (LNLS, Campinas). Seven samples were analyzed: Mn, Mn2O3, Fe, Fe2O3, Cu, CuO, Cu2O using monochromatic synchrotron radiation to determine experimentally the cross sections of the resonant Raman effect as a function of the incident energy; energy scannings were carried out in different ranges of energies near the absorption edge of the target element. According to our results, the cross sections for pure samples are similar to those for oxides, showing that the Raman scattering takes place in the same way in both kinds of samples.