Effect of Pressure on Valence and Structural Properties of YbFe₂Ge₂ Heavy Fermion Compound A Combined Inelastic X-ray Spectroscopy, X-ray Diffraction, and Theoretical Investigation

Journal Article · Fri Jun 03 00:00:00 EDT 2016 · Inorganic Chemistry

DOI:https://doi.org/10.1021/acs.inorgchem.5b01534· OSTI ID:1227024

Kumar, Ravhi S. ^[1]; Svane, Axel ^[2]; Vaitheeswaran, Ganapathy ^[3]; Kanchana, Venkatakrishnan ^[4]; Antonio, Daniel ^[1]; Cornelius, Andrew L. ^[1]; Bauer, Eric D. ^[5]; Xiao, Yuming ^[6]; Chow, Paul ^[6]

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1. Univ. of Nevada, Las Vegas, NV (United States)
2. Aarhus Univ. (Denmark)
3. Univ. of Hyderabad, Telengana (India)
4. Indian Inst. of Technology (IIT), Madras (India)
5. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
6. Argonne National Lab. (ANL), Argonne, IL (United States)

The crystal structure and the Yb valence of the YbFe₂Ge₂ heavy fermion compound was measured at room temperature and under high pressures using high-pressure powder X-ray diffraction and X-ray absorption spectroscopy via both partial fluorescence yield and resonant inelastic X-ray emission techniques. Furthermore, the measurements are complemented by first-principles density functional theoretical calculations using the self-interaction corrected local spin density approximation investigating in particular the magnetic structure and the Yb valence. While the ThCr₂Si₂-type tetragonal (I4/mmm) structure is stable up to 53 GPa, the X-ray emission results show an increase of the Yb valence from v = 2.72(2) at ambient pressure to v = 2.93(3) at ~9 GPa, where at low temperature a pressure-induced quantum critical state was reported.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
• Sponsoring Organization: USDOE
• OSTI ID: 1227024
• Journal Information: Inorganic Chemistry, Vol. 54, Issue 21; ISSN 0020-1669
• Country of Publication: United States
• Language: ENGLISH