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1. Phase Stability and Thermal Equation of State of Iron Carbide Fe 3 C to 245 GPa

   https://doi.org/10.1029/2019GL084545  

   Hu, Xiaojun ; Fei, Yingwei ; Yang, Jing ; Cai, Yang ; Ye, Shijia ; Qi, Meilan ; Liu, Fusheng ; Zhang, Mingjian ( October 2019 , Geophysical Research Letters)

   We conducted shock wave experiments on iron carbide Fe₃C up to a Hugoniot pressure of 245 GPa. The correlation between the particle velocity (u_p) and shock wave velocity (u_s) can be fitted into a linear relationship,u_s= 4.627(±0.073) + 1.614(±0.028)u_p. The density‐pressure relationship is consistent with a single‐phase compression without decomposition. The inference is further supported by the comparison of the observed Hugoniot density with the calculated Hugoniot curves of possible decomposition products. The new Hugoniot data combined with the reported 300‐K isothermal compression data yielded a Grüneisen parameter ofγ= 2.23(7.982/ρ)^0.29. The thermal equation of state of Fe₃C is further used to calculate the density profile of Fe₃C along the Earth's adiabatic geotherm. The density of Fe₃C was found to be too low (by ~5%) to match the observed density in the Earth's inner core, and Fe₃C is unlikely a dominant component of the inner core.

    

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2. Si-integrated ultrathin films of phase-pure Y 3 Fe 5 O 12 (YIG) via novel two-step rapid thermal anneal

   https://doi.org/10.1080/21663831.2017.1295285  

   Gage, Thomas E. ; Dulal, Prabesh ; Solheid, Peter A. ; Flannigan, David J. ; Stadler, Bethanie J. H. ( March 2017 , Materials Research Letters)
3. Reaction Dynamics Study of the Molecular Hydrogen Loss Channel in the Elementary Reactions of Ground-State Silicon Atoms (Si( 3 P)) With 1- and 2-Methyl-1,3-Butadiene (C 5 H 8 )

   https://doi.org/10.1021/acs.jpca.1c03023  

   Yang, Zhenghai ; He, Chao ; Goettl, Shane ; Kaiser, Ralf I. ( June 2021 , The Journal of Physical Chemistry A)
4. High-pressure phase transition in Y 3 Fe 5 O 12

   https://doi.org/10.1088/0953-8984/27/40/405401  

   Stan, C. V. ; Wang, J. ; Zouboulis, I. S. ; Prakapenka, V. ; Duffy, T. S. ( September 2015 , Journal of Physics: Condensed Matter)
5. Synthesis and Stability of an Eight‐Coordinated Fe 3 O 4 High‐Pressure Phase: Implications for the Mantle Structure of Super‐Earths

   https://doi.org/10.1029/2022JE007344  

   Zurkowski, C. C. ; Yang, J. ; Chariton, S. ; Prakapenka, V. B. ; Fei, Y. ( August 2022 , Journal of Geophysical Research: Planets)

   Super‐Earths ranging up to 10 Earth masses (M_E) with Earth‐like density are common among the observed exoplanets thus far, but their measured masses and radii do not uniquely elucidate their internal structure. Exploring the phase transitions in the Mg‐silicates that define the mantle‐structure of super‐Earths is critical to characterizing their interiors, yet the relevant terapascal conditions are experimentally challenging for direct structural analysis. Here we investigated the crystal chemistry of Fe₃O₄as a low‐pressure analog to Mg₂SiO₄between 45–115 GPa and up to 3000 K using powder and single crystal X‐ray diffraction in the laser‐heated diamond anvil cell. Between 60–115 GPa and above 2000 K, Fe₃O₄adopts an 8‐fold coordinated Th₃P₄‐type structure (I‐43d,Z = 4) with disordered Fe²⁺and Fe³⁺into one metal site. This Fe‐oxide phase is isostructural with that predicted for Mg₂SiO₄above 500 GPa in super‐Earth mantles and suggests that Mg₂SiO₄can incorporate both ferric and ferrous iron at these conditions. The pressure‐volume behavior observed in this 8‐fold coordinated Fe₃O₄indicates a maximum 4% density increase across the 6‐ to 8‐fold coordination transition in the analog Mg‐silicate. Reassessment of the FeO—Fe₃O₄fugacity buffer considering the Fe₃O₄phase relationships identified in this study reveals that increasing pressure and temperature to 120 GPa and 3000 K in Earth and planetary mantles drives iron toward oxidation.

    

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