Abstract
Molecular dynamics simulations and first-principles electronic structure calculations are used to study the structural behavior of orthoenstatite, MgSiO3, at high pressures. The calculations suggest two possible high-pressure polymorphs of orthoenstatite, one with P21ca and the other with Pbca symmetry. Both polymorphs are structurally related to orthoenstatite. Molecular dynamics simulations reveal the displacive nature of the phase transitions between the three phases. Electronic structure calculations predict a phase transition from orthoenstatite to the metastable P21ca structure at 9 GPa, which may explain the anomalies in elastic and vibrational properties observed experimentally. A second metastable transition from the P21ca to the high-pressure Pbca structure may be observable above 20 GPa.
© 2015 by Walter de Gruyter Berlin/Boston
Articles in the same Issue
- Compositional variability and crystal structural features of guanacoite
- Interferometric study of pyrite surface reactivity in acidic conditions
- White mica domain formation: A model for paragonite, margarite, and muscovite formation during prograde metamorphism
- High-pressure phase transitions in MgSiO3 orthoenstatite studied by atomistic computer simulation
- Time-resolved synchrotron powder X-ray diffraction study of magnetite formation by the Fe(III)-reducing bacterium Geobacter sulfurreducens
- Low-temperature calorimetric and magnetic data for natural end-members of the axinite group
- Temperature derivatives of elastic wave velocities in plagioclase (An51±1) above and below the order-disorder transition temperature
- Disordered silica with tridymite-like structure in the Twiggs clay
- Crystal structures of synthetic melanotekite (Pb2Fe2Si2O9), kentrolite (Pb2Mn2Si2O9), and the aluminum analogue (Pb2Al2Si2O9)
- Structure and reactivity of synthetic Co-substituted goethites
- The crystal chemistry of Fe-bearing sphalerites: An infrared spectroscopic study
- Effects of hydration on the structure and compressibility of wadsleyite, β-(Mg2SiO4)
- Metastability of sillimanite relative to corundum and quartz in the kyanite stability field: Competition between stable and metastable reactions
- Diffusion, discontinuous precipitation, metamorphism, and metasomatism: The complex history of South African upper-mantle symplectites
- Thermal behavior of a Ti-rich phlogopite from Mt. Vulture (Potenza, Italy): An in situ X-ray single-crystal diffraction study
- The high-pressure behavior of an Al- and Fe-rich natural orthopyroxene
- High-pressure phase relation of MnSiO3 up to 85 GPa: Existence of MnSiO3 perovskite
- Linking Mössbauer and structural parameters in elbaite-schorl-dravite tourmalines
- Synchrotron powder X-ray diffraction study of the structure and dehydration behavior of palygorskite
- Maskelynite-hosted apatite in the Chassigny meteorite: Insights into late-stage magmatic volatile evolution in martian magmas
- Eskolaite associated with diamond from the Udachnaya kimberlite pipe, Yakutia, Russia
- Lakebogaite, CaNaFe23+H(UO2)2(PO4)4(OH)2(H2O)8, a new uranyl phosphate with a unique crystal structure from Victoria, Australia
- Letter. Crystal structure and Raman spectrum of hydroxyl-bästnasite-(Ce), CeCO3(OH)
Articles in the same Issue
- Compositional variability and crystal structural features of guanacoite
- Interferometric study of pyrite surface reactivity in acidic conditions
- White mica domain formation: A model for paragonite, margarite, and muscovite formation during prograde metamorphism
- High-pressure phase transitions in MgSiO3 orthoenstatite studied by atomistic computer simulation
- Time-resolved synchrotron powder X-ray diffraction study of magnetite formation by the Fe(III)-reducing bacterium Geobacter sulfurreducens
- Low-temperature calorimetric and magnetic data for natural end-members of the axinite group
- Temperature derivatives of elastic wave velocities in plagioclase (An51±1) above and below the order-disorder transition temperature
- Disordered silica with tridymite-like structure in the Twiggs clay
- Crystal structures of synthetic melanotekite (Pb2Fe2Si2O9), kentrolite (Pb2Mn2Si2O9), and the aluminum analogue (Pb2Al2Si2O9)
- Structure and reactivity of synthetic Co-substituted goethites
- The crystal chemistry of Fe-bearing sphalerites: An infrared spectroscopic study
- Effects of hydration on the structure and compressibility of wadsleyite, β-(Mg2SiO4)
- Metastability of sillimanite relative to corundum and quartz in the kyanite stability field: Competition between stable and metastable reactions
- Diffusion, discontinuous precipitation, metamorphism, and metasomatism: The complex history of South African upper-mantle symplectites
- Thermal behavior of a Ti-rich phlogopite from Mt. Vulture (Potenza, Italy): An in situ X-ray single-crystal diffraction study
- The high-pressure behavior of an Al- and Fe-rich natural orthopyroxene
- High-pressure phase relation of MnSiO3 up to 85 GPa: Existence of MnSiO3 perovskite
- Linking Mössbauer and structural parameters in elbaite-schorl-dravite tourmalines
- Synchrotron powder X-ray diffraction study of the structure and dehydration behavior of palygorskite
- Maskelynite-hosted apatite in the Chassigny meteorite: Insights into late-stage magmatic volatile evolution in martian magmas
- Eskolaite associated with diamond from the Udachnaya kimberlite pipe, Yakutia, Russia
- Lakebogaite, CaNaFe23+H(UO2)2(PO4)4(OH)2(H2O)8, a new uranyl phosphate with a unique crystal structure from Victoria, Australia
- Letter. Crystal structure and Raman spectrum of hydroxyl-bästnasite-(Ce), CeCO3(OH)