Jump to ContentJump to Main Navigation
Show Summary Details
More options …

American Mineralogist

Journal of Earth and Planetary Materials

Ed. by Baker, Don / Xu, Hongwu / Swainson, Ian


IMPACT FACTOR 2018: 2.631

CiteScore 2018: 2.55

SCImago Journal Rank (SJR) 2018: 1.355
Source Normalized Impact per Paper (SNIP) 2018: 1.103

Online
ISSN
1945-3027
See all formats and pricing
More options …
Volume 99, Issue 8-9

Issues

Chemistry and Mineralogy of Earth’s Mantle. The spin state of iron in Fe3+-bearing Mg-perovskite and its crystal chemistry at high pressure

Izumi Mashino
  • Department of Earth and Planetary Materials Science, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Eiji Ohtani
  • Department of Earth and Planetary Materials Science, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
  • V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch, Russian Academy of Sciences, Koptyuga Avenue, 3, Novosibirsk, 630090, Russia
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Naohisa Hirao / Takaya Mitsui / Ryo Masuda / Makoto Seto / Takeshi Sakai
  • Department of Earth and Planetary Materials Science, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
  • Geodynamics Research Center, Ehime University, Matsuyama 790-8577, Japan
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Suguru Takahashi
  • Department of Earth and Planetary Materials Science, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Satoshi Nakano
Published Online: 2014-08-12 | DOI: https://doi.org/10.2138/am.2014.4659

Abstract

Valence, spin states, and crystallographic sites of Fe in (Mg,Fe)SiO3 perovskite were investigated using energy-domain 57Fe-synchrotron Mössbauer spectroscopy and powder X-ray diffraction up to 86 GPa. The volumes of Fe3+-bearing perovskite in this study are slightly smaller than those of Mg endmember perovskite. Our Mössbauer data suggest that Fe3+ prefers A sites coupled with Mg vacancies, which is consistent with previous data at ambient conditions. Fe3+ in the A site remains in a high-spin state up to 86 GPa, and some fraction of the A site is occupied by Fe2+ at pressures above 30 GPa. Fe2+ in the A sites is also in a high-spin state up to 86 GPa. The coupled substitution from Mg2+ to a highspin state of Fe3+ and Mg2+ vacancy would make the volume of perovskite smaller than that of Mg end-member perovskite. If the lower mantle is saturated in silica, perovskite containing high-spin Fe3+ in A site has a higher density. Such silica oversaturated regions could sink by the density difference.

Keywords: Perovskite; ferric iron; spin state; Mössbauer spectroscopy; X-ray diffraction

About the article

Published Online: 2014-08-12

Published in Print: 2014-08-01


Citation Information: American Mineralogist, Volume 99, Issue 8-9, Pages 1555–1561, ISSN (Online) 1945-3027, ISSN (Print) 0003-004X, DOI: https://doi.org/10.2138/am.2014.4659.

Export Citation

© 2014 by Walter de Gruyter Berlin/Boston.

Comments (0)

Please log in or register to comment.
Log in