INVESTIGADORES
SANCHEZ Hector Jorge
artículos
Título:
X-Ray Resonant Raman Scattering Cross-Sections of Mn, Fe, Cu and Zn
Autor/es:
HECTOR JORGE SANCHEZ; M.C. VALENTINUZZI; C. A. PÉREZ
Revista:
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
Editorial:
IOP PUBLISHING LTD
Referencias:
Año: 2006 vol. 39 p. 4317 - 4327
ISSN:
0953-4075
Resumen:
X-ray fluorescence spectra present singular characteristics produced by the
different scattering processes. When atoms are irradiated with incident energy
lower and close to an absorption edge, scattering peaks appear due to an inelastic
process known as resonant Raman scattering. It constitutes an important
contribution to the background of the fluorescent line. The resonant Raman
scattering must be taken into account in the determination of low concentration
contaminants, especially when the elements have proximate atomic numbers.
The values of the mass attenuation coefficients experimentally obtained when
materials are analysed with monochromatic x-ray beams under resonant
conditions differ from the theoretical values (between 5% and 10%). This
difference is due, in part, to the resonant Raman scattering. Monochromatic
synchrotron radiation was used to study the Raman effect on pure samples
of Mn, Fe, Cu and Zn. Energy scans were carried out in different ranges of
energy near the absorption edge of the target element. As the Raman peak has
a non-symmetric shape, theoretical models for the differential cross section,
convoluted with the instrument function, were used to determine the RRS cross
section as a function of the incident energy.