Real-part EXAFS from multilayer Bragg reflections: a promising new EXAFS technique

Resonant X-ray scattering measurements on the energy dependence of multilayer Bragg reflections are presented. It is shown that the deviations from the ideal Bragg law at resonance are due to refraction, which allows a determination of the real part of the extended X-ray absorption fine-structure (EXAFS) function. With this new technique, it is possible to obtain phase-sensitive EXAFS information without the di cult data analysis and absorption corrections required by the diffraction anomalous fine-structure technique.