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Updated: Mar 25, 2026

High Pressure Single Crystal Diffraction at PX^2
Published on: January 16, 2017
High pressure effects on U L3 x-ray absorption in partial fluorescence yield mode and single crystal x-ray
Farzana Nasreen1, Daniel Antonio1, Derrick VanGennep2
1High Pressure Science and Engineering Center (HiPSEC) and Department of Physics and Astronomy, University of Nevada, Las Vegas, NV 89154, USA.
Abstract:
We report a study of high pressure x-ray absorption (XAS) performed in the partial fluorescence yield mode (PFY) at the U L3 edge (0–28.2 GPa) and single crystal x-ray diffraction (SXD) (0–20 GPa) on the UCd11 heavy fermion compound at room temperature. Under compression, the PFY-XAS results show that the white line is shifted by +4.1(3) eV at the highest applied pressure of 28.2 GPa indicating delocalization of the 5f electrons. The increase in full width at half maxima and decrease in relative amplitude of the white line with respect to the edge jump point towards 6d band broadening under high pressure. A bulk modulus of K0 = 62(1) GPa and its pressure derivative, K0 = 4.9(2) was determined from high pressure SXD results. Both the PFY-XAS and diffraction results do not show any sign of a structural phase transition in the applied pressure range.
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