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DOE OSTI · 1781296

Accurate temperature determination from XRD and EXAFS measurements (Full Technical Final Report)

Coppari, Federica
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Abstract

Measuring temperature is of fundamental importance for High Energy Density science (HED), for studying melting, phase transitions and equations of state. However, temperature determination of high pressure and high temperature (0.1-1 eV) condensed matter remains one of the biggest challenges in such experiments. This project used a combination of advanced experimental techniques and state-of-the-art computational methods to construct a framework relating the observed attenuation of X-ray diffraction (XRD) and Extended X-ray Absorption Fine Structure (EXAFS) signals due to thermal fluctuations to the actual temperature achieved in the experiments. This approach was benchmarked against low temperature resistive heating diamond anvil cell (DAC) experiments and cross-validated at higher pressure and temperature by combining the two complementary and independent techniques, diffraction and EXAFS.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS

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Coppari, Federica. 2021-04-28. Accurate temperature determination from XRD and EXAFS measurements (Full Technical Final Report). https://doi.org/10.2172/1781296

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