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DOE OSTI · 2527366

Continuous Evolution of Eu 2+ /Eu 3+ Mixed Valency Driven by Pressure and Temperature

Xu, Mingyu [Michigan State University, East Lansing, MI (United States)]·Jose, Greeshma C. [University of Alabama, Birmingham, AL (United States)]·Cheng, Mouyang [Massachusetts Institute of Technology (MIT), Cambridge, MA (United States)]·Peng, Cheng [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000289772749)·Gonzalez Jimenez, Jose L. [Michigan State University, East Lansing, MI (United States)]·Bi, Wenli [University of Alabama, Birmingham, AL (United States)]·Li, Mingda [Massachusetts Institute of Technology (MIT), Cambridge, MA (United States)] (ORCID:0000000270556368)·Xie, Weiwei [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000255008195)
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Abstract

Continuous mixed valency involving Eu 2+ and Eu 3+ in Eu 4 Bi 6 Se 13 can be induced under applied pressure or at reduced temperatures. The monoclinic structure of Eu 4 Bi 6 Se 13 , crystallizing in the P2 1 /m space group (No. 11), features linear chains of Eu atoms aligned along the b-axis. Magnetic susceptibility measurements, conducted both parallel and perpendicular to the b-axis and analyzed using Curie–Weiss theory, alongside high-pressure partial fluorescence yield (PFY) data from X-ray absorption spectroscopy (XAS), indicate the material’s propensity to adopt a mixed-valent state. Within this state, the trivalent Eu 3+ configuration becomes increasingly favored as the pressure rises or the temperature decreases.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYDiffractionFluorescenceLatticesMagnetic propertiesX-rays

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Xu, Mingyu [Michigan State University, East Lansing, MI (United States)], Jose, Greeshma C. [University of Alabama, Birmingham, AL (United States)], Cheng, Mouyang [Massachusetts Institute of Technology (MIT), Cambridge, MA (United States)], Peng, Cheng [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000289772749), Gonzalez Jimenez, Jose L. [Michigan State University, East Lansing, MI (United States)], Bi, Wenli [University of Alabama, Birmingham, AL (United States)], Li, Mingda [Massachusetts Institute of Technology (MIT), Cambridge, MA (United States)] (ORCID:0000000270556368), Xie, Weiwei [Michigan State University, East Lansing, MI (United States)] (ORCID:0000000255008195). 2025-02-25. Continuous Evolution of Eu 2+ /Eu 3+ Mixed Valency Driven by Pressure and Temperature. https://doi.org/10.1021/acs.jpca.4c08660

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