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Title: Compressional behavior of omphacite to 47 GPa

Authors:
; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
National Science Foundation (NSF)
OSTI Identifier:
1274746
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics and Chemistry of Minerals; Journal Volume: 2016; Journal Issue: 2016
Country of Publication:
United States
Language:
ENGLISH

Citation Formats

Zhang, Dongzhou, Hu, Yi, and Dera, Przemyslaw K. Compressional behavior of omphacite to 47 GPa. United States: N. p., 2016. Web. doi:10.1007/s00269-016-0827-4.
Zhang, Dongzhou, Hu, Yi, & Dera, Przemyslaw K. Compressional behavior of omphacite to 47 GPa. United States. doi:10.1007/s00269-016-0827-4.
Zhang, Dongzhou, Hu, Yi, and Dera, Przemyslaw K. 2016. "Compressional behavior of omphacite to 47 GPa". United States. doi:10.1007/s00269-016-0827-4.
@article{osti_1274746,
title = {Compressional behavior of omphacite to 47 GPa},
author = {Zhang, Dongzhou and Hu, Yi and Dera, Przemyslaw K.},
abstractNote = {},
doi = {10.1007/s00269-016-0827-4},
journal = {Physics and Chemistry of Minerals},
number = 2016,
volume = 2016,
place = {United States},
year = 2016,
month = 7
}
  • Omphacite is an important mineral component of eclogite. Single crystal synchrotron X-ray diffraction data on natural (Ca,Na)(Mg,Fe,Al)Si 2O 6 omphacite have been collected at the Advanced Photon Source beamlines 13-BM-C and 13-ID-D up to 47 GPa at ambient temperature. Unit cell parameter and crystal structure refinements were carried out to constrain the isothermal equation of state and compression mechanism. The 3rd order Birch-Murnaghan equation of state (BM3) fit of all data gives V o = 423.9(3) Å3, K To = 116(2) GPa and K To’ = 4.3(2). These elastic parameters are consistent with the general trend of the diopside-jadeite join.more » The eight-coordinated polyhedra (M2 and M21) are the most compressible, and contribute to majority of the unit cell compression, while the SiO 4 tetrahedra (Si1 and Si2) behave as rigid structural units and are the most incompressible. Axial compressibilities are determined by fitting linearized BM 3 equation of state to pressure dependences of unit cell parameters. Throughout the investigated pressure range, the b-axis is more compressible than the c-axis. Here, the axial compressibility of the α-axis is the largest among the three axes at 0 GPa, yet it quickly drops to the smallest at pressures above 5 GPa, which is explained by the rotation of the stiffest compression axis toward the a-axis with the increase of pressure.« less
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