The partial pair distribution function (PPDF) of an amorphous material is the local environment of an element in the solid. For a two-component system, such as MoGe3, there are three PPDFs: Mo-Mo, Ge-Ge, and Mo-Ge. The PPDF can be derived from anomalous scattering measurements of the material, in this case collecting data near both the Mo and Ge K-absorption edges. Successful derivation of the PPDFs requires the removal of a number of error signals from the x-rays scattered from the sample. In addition to the elastically scattered light, there are both resonant Raman and Compton scattering. Although the resonant Raman Kα signal can be resolved using a solid-state detector, the resonant Raman Kβ and Compton signals cannot. We have developed a variable focal length graphite analyzer which disperses these signals onto a position-sensitive detector. At each scattering angle, a spectrum of the scattered energies is recorded. These spectra are then deconvolved and the elastic signal is integrated. In this paper we present the design and implementation of the analyzer, discussing error sources such as focusing and mechanical compliance.
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