Resonant Anomlous X-ray Reflectivity (RAXR)
Resonant anomalous X-ray reflectivity (RAXR) makes use of the ‘anomolous’
dispersion in the atomic scattering factor of an atom near its characteristic
absorption
edge. This allows for the possibility of incorporating element-specific information
into
the X-ray scattering methods. Both the real (f’) and imaginary (f’’) parts of
the
scattering factor are modified which are related to each other by Kramers-Kronig
relations. The imaginary part of the resonant scattering factor, f’’(E) is proportional
to the X-ray absorption near edge structure (XANES) profile that could be measured
in X-ray absorption spectroscopy. Consequently RAXR brings together the
unprecedented structural sensitivity and interfacial specificity of X-ray reflectivity
measurements with the element-specificity and spectroscopic sensitivity of XANES
measurements leading to a much more complete understanding of the complex
structural and chemical changes of many important interfacial processes.