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Title: High-Pressure Study of Perovskites and Postperovskites in the (Mg,Fe)GeO 3 System

Abstract

The effect of incorporation of Fe 2+ on the perovskite (Pbnm) and postperovskite (Cmcm) structures was investigated in the (Mg,Fe)GeO 3 system at high pressures and temperatures using laser-heated diamond anvil cell and synchrotron X-ray diffraction. Samples with compositions of Mg# ≥ 48 were shown to transform to the perovskite (~30 GPa and ~1500 K) and postperovskite (>55 GPa, ~1600–1800 K) structures. Compositions with Mg# ≥ 78 formed single-phase perovskite and postperovskite, whereas those with Mg# < 78 showed evidence for partial decomposition. The incorporation of Fe into the perovskite structure causes a decrease in octahedral distortion as well as a modest decrease in bulk modulus (K 0) and a modest increase in zero-pressure volume (V 0). It also leads to a decrease in the perovskite-to-postperovskite phase transition pressure by ~9.5 GPa over compositions from Mg#78 to Mg#100.

Authors:
ORCiD logo [1];  [2];  [3];  [4];  [2]
  1. Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States; Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
  2. Department of Geosciences, Princeton University, Princeton, New Jersey 08544, United States
  3. Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
  4. GeoSoilEnviroCARS, University of Chicago, Argonne National Lab, Argonne, Illinois 60439, United States
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
DOE - BASIC ENERGY SCIENCESNSF
OSTI Identifier:
1372253
Resource Type:
Journal Article
Resource Relation:
Journal Name: Inorganic Chemistry; Journal Volume: 56; Journal Issue: 14
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Stan, Camelia V., Dutta, Rajkrishna, Cava, Robert J., Prakapenka, Vitali B., and Duffy, Thomas S. High-Pressure Study of Perovskites and Postperovskites in the (Mg,Fe)GeO 3 System. United States: N. p., 2017. Web. doi:10.1021/acs.inorgchem.7b00774.
Stan, Camelia V., Dutta, Rajkrishna, Cava, Robert J., Prakapenka, Vitali B., & Duffy, Thomas S. High-Pressure Study of Perovskites and Postperovskites in the (Mg,Fe)GeO 3 System. United States. doi:10.1021/acs.inorgchem.7b00774.
Stan, Camelia V., Dutta, Rajkrishna, Cava, Robert J., Prakapenka, Vitali B., and Duffy, Thomas S. 2017. "High-Pressure Study of Perovskites and Postperovskites in the (Mg,Fe)GeO 3 System". United States. doi:10.1021/acs.inorgchem.7b00774.
@article{osti_1372253,
title = {High-Pressure Study of Perovskites and Postperovskites in the (Mg,Fe)GeO 3 System},
author = {Stan, Camelia V. and Dutta, Rajkrishna and Cava, Robert J. and Prakapenka, Vitali B. and Duffy, Thomas S.},
abstractNote = {The effect of incorporation of Fe2+ on the perovskite (Pbnm) and postperovskite (Cmcm) structures was investigated in the (Mg,Fe)GeO3 system at high pressures and temperatures using laser-heated diamond anvil cell and synchrotron X-ray diffraction. Samples with compositions of Mg# ≥ 48 were shown to transform to the perovskite (~30 GPa and ~1500 K) and postperovskite (>55 GPa, ~1600–1800 K) structures. Compositions with Mg# ≥ 78 formed single-phase perovskite and postperovskite, whereas those with Mg# < 78 showed evidence for partial decomposition. The incorporation of Fe into the perovskite structure causes a decrease in octahedral distortion as well as a modest decrease in bulk modulus (K0) and a modest increase in zero-pressure volume (V0). It also leads to a decrease in the perovskite-to-postperovskite phase transition pressure by ~9.5 GPa over compositions from Mg#78 to Mg#100.},
doi = {10.1021/acs.inorgchem.7b00774},
journal = {Inorganic Chemistry},
number = 14,
volume = 56,
place = {United States},
year = 2017,
month = 6
}
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