X-ray scattering total scattering at high pressure (Invited)
Abstract
The determination of the atomic arrangement in complex crystalline, disordered or nanostructured materials is challenging, since the local atomic arrangement often differs from the average configuration constraint by space-group symmetry. The macroscopic physical properties are frequently critically affected by particle size and/or subtle deviation of the local-structure from the average crystal structure. The tool of choice for determination of the local structure has been extended X-ray absorption fine structure (EXAFS) spectroscopy, which probes the atomic arrangement in the first few coordination shells around an atom. However, the limited distance range is insufficient for the analysis of intermediate range structural heterogeneities. Recently, X-ray total scattering with subsequent analysis of the pair distribution function has been proven to be a valuable method to probe the local, intermediate and long range atomic structure of materials. The pair distribution function is derived from the total elastic X-ray scattering, the sum of Bragg and diffuse scattering, via Fourier transformation of the normalized total scattering intensity. However, measuring the total elastic scattering of a sample at high pressure, which is necessary for pair distribution function analysis, is technically very challenging. The power and limitations of the X-ray total scattering at high pressure will be discussed.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2013
- Bibcode:
- 2013AGUFMMR51A..08E
- Keywords:
-
- 3924 MINERAL PHYSICS High-pressure behavior;
- 3954 MINERAL PHYSICS X-ray;
- neutron;
- and electron spectroscopy and diffraction;
- 3994 MINERAL PHYSICS Instruments and techniques