Partial pair distribution functions obtained without regularization from pha-MoGe3 by anomalous x-ray scattering
Abstract
We present partial pair distribution functions (PPDFs) obtained by anomalous (resonant) x-ray scattering for pha-MoGe_3, an endpoint for phase separation in the Ge-rich amorphous Mo-Ge alloys. These alloys display a metal-insulator transition believed to be due to percolation of the conducting phase, MoGe_3. This composition is unexpected since the nearest equilibrium compound is MoGe_2. Extracting fully-chemically-specific structure, the PPDFs, for an amorphous alloy is notoriously difficult since the matrix equation involved is ill-conditioned so that experimental and other errors are magnified significantly. To minimize errors associated with inelastic scattering, a variable-focus, dispersive analyzer and position-sensitive detector have been employed to isolate the elastic scattering experimentally. PPDFs calculated from the data without regularization are much more reliable than those obtained with lower energy resolution detectors and allow interpretation of the physical results. A description of local coordination environment and discussion of the relevance of MoGe3 composition will be presented.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2002
- Bibcode:
- 2002APS..MARX25006I