Phonon density of states of Fe2O3 across high-pressure structural and electronic transitions

Journal Article · Wed Aug 24 00:00:00 EDT 2011 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PhysRevB.84.064424· OSTI ID:1065607

Lin, Jung-Fu ^[1]; Tse, John S. ^[2]; Alp, Esen E. ^[3]; Zhao, Jiyong ^[3]; Lerche, Michael; Sturhahn, Wolfgang ^[3]; Xiao, Yuming ^[4]; Chow, Paul ^[4]

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1. University of Texas, Austin, TX (United States)
2. Univ. of Saskatchewan, Saskatoon, Saskatchewan (Canada)
3. Argonne National Laboratory (ANL), Argonne, IL (United States)
4. PCAT, Carnegie Institution of Washington, Advanced Photon Source, Argonne National Laboratory (ANL), Argonne, IL (United States)

High-pressure phonon density of states (PDOS) of Fe₂O₃ across structural and electronic transitions has been investigated by nuclear resonant inelastic x-ray scattering (NRIXS) and first-principles calculations together with synchrotron Mössbauer, x-ray diffraction, and x-ray emission spectroscopies. Drastic changes in elastic, thermodynamic, and vibrational properties of Fe₂O₃ occur across the Rh₂O₃(II)-type structural transition at 40–50 GPa, whereas the Mott insulator-metal transition occurring after the structural transition only causes nominal changes in the properties of the Fe₂O₃. The observed anomalous mode-softening behavior of the elastic constants is associated with the structural transition at 40–50 GPa, leading to substantial changes in the Debye-like part of the PDOS in the terahertz acoustic phonons. Our experimental and theoretical studies provide new insights into the effects of the structural and electronic transitions in the transition-metal oxide (TMO) compounds.

• Research Organization: Energy Frontier Research Centers (EFRC) (United States). Energy Frontier Research in Extreme Environments (EFree)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• DOE Contract Number: SC0001057
• OSTI ID: 1065607
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 84, Issue 6; Related Information: EFree partners with Carnegie Institution of Washington (lead); California Institute of Technology; Colorado School of Mines; Cornell University; Lehigh University; Pennsylvania State University; ISSN 1098-0121
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
catalysis (heterogeneous)
solar (photovoltaic)
phonons
thermoelectric
energy storage (including batteries and capacitors)
hydrogen and fuel cells
superconductivity
charge transport
mesostructured materials
materials and chemistry by design
synthesis (novel materials)