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Title: Substitution and diffusion of Cr 2+ and Cr 3+ in synthetic forsterite and natural olivine at 1200–1500 °C and 1 bar

Abstract

The diffusion and substitution mechanisms of Cr in forsterite were studied as a function of crystallographic orientation and the chemical potentials of all four components in the system MgO-SiO2-Cr-O. Oxygen fugacity (fO2) was varied over 15.4 log units at 1400 °C and was fixed at the iron-wüstite equilibrium for a temperature series (1200–1500 °C). The valence state changes of Cr along some diffusion profiles was also investigated using X-ray absorption near edge structure spectroscopy.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
FOREIGN
OSTI Identifier:
1417384
Resource Type:
Journal Article
Resource Relation:
Journal Name: Geochimica et Cosmochimica Acta; Journal Volume: 220; Journal Issue: C
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Jollands, M. C., O'Neill, H. St. C., Van Orman, J., Berry, A. J., Hermann, J., Newville, M., and Lanzirotti, A.. Substitution and diffusion of Cr 2+ and Cr 3+ in synthetic forsterite and natural olivine at 1200–1500 °C and 1 bar. United States: N. p., 2018. Web. doi:10.1016/j.gca.2017.09.030.
Jollands, M. C., O'Neill, H. St. C., Van Orman, J., Berry, A. J., Hermann, J., Newville, M., & Lanzirotti, A.. Substitution and diffusion of Cr 2+ and Cr 3+ in synthetic forsterite and natural olivine at 1200–1500 °C and 1 bar. United States. doi:10.1016/j.gca.2017.09.030.
Jollands, M. C., O'Neill, H. St. C., Van Orman, J., Berry, A. J., Hermann, J., Newville, M., and Lanzirotti, A.. Mon . "Substitution and diffusion of Cr 2+ and Cr 3+ in synthetic forsterite and natural olivine at 1200–1500 °C and 1 bar". United States. doi:10.1016/j.gca.2017.09.030.
@article{osti_1417384,
title = {Substitution and diffusion of Cr 2+ and Cr 3+ in synthetic forsterite and natural olivine at 1200–1500 °C and 1 bar},
author = {Jollands, M. C. and O'Neill, H. St. C. and Van Orman, J. and Berry, A. J. and Hermann, J. and Newville, M. and Lanzirotti, A.},
abstractNote = {The diffusion and substitution mechanisms of Cr in forsterite were studied as a function of crystallographic orientation and the chemical potentials of all four components in the system MgO-SiO2-Cr-O. Oxygen fugacity (fO2) was varied over 15.4 log units at 1400 °C and was fixed at the iron-wüstite equilibrium for a temperature series (1200–1500 °C). The valence state changes of Cr along some diffusion profiles was also investigated using X-ray absorption near edge structure spectroscopy.},
doi = {10.1016/j.gca.2017.09.030},
journal = {Geochimica et Cosmochimica Acta},
number = C,
volume = 220,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2018},
month = {Mon Jan 01 00:00:00 EST 2018}
}
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