XAFS

Shell fitting of extended X-ray absorption fine structure (EXAFS) is commonly done in Artemis, part of the Demeter package. Athena turns an experimental spectrum into a file Artemis can import. Artemis then lines the measured oscillation up with scattering paths from FEFF, and from that estimates the coordination number $N$, a distance correction, the disorder $\sigma^2$, and the energy-origin shift $\Delta E_0$. The interface, the order of operations, and three examples are kept apart below....

All-solid-state lithium-ion batteries (ASSLIBs) replace the liquid electrolyte with a solid electrolyte (SE). Both the electrodes and the electrolyte are solids, so the interfaces are buried. Side reactions, poor contact, and lithium dendrites are hard to see directly. Synchrotron X-rays can do diffraction, absorption spectroscopy, and imaging in the same facility, which is why they are used to watch bulk ion transport and how a solid–solid interface changes during cycling. The cases below ar...