Skip to Main Content
Skip Nav Destination

The spin state of Fe (super 3+) in lower mantle bridgmanite

Ryosuke Sinmyo, Catherine McCammon and Leonid Dubrovinsky
The spin state of Fe (super 3+) in lower mantle bridgmanite
American Mineralogist (June 2017) 102 (6): 1263-1269


Iron- and aluminum-bearing MgSiO (sub 3) bridgmanite is the most abundant mineral in the Earth's interior; hence its crystal chemistry is fundamental to expanding our knowledge of the deep Earth and its evolution. In this study, the valence and spin state of iron in well-characterized Al-free Fe (super 3+) -rich bridgmanite were investigated by means of Mossbauer spectroscopy to understand the effect of ferric iron on the spin state. We found that a minor amount of Fe (super 3+) is in the low-spin state above 36 GPa and that its proportion does not increase substantially with pressure up to 83 GPa. This observation is consistent with recent experimental studies that used Mossbauer and X-ray emission spectroscopy. In the Earth's deep lower mantle, Fe (super 3+) spin crossover may take place at depths below 900 and 1200 km in pyrolite and MORB, respectively. However, the effect of spin crossover on physical properties may be small due to the limited amount of Fe (super 3+) in the low-spin state.

ISSN: 0003-004X
EISSN: 1945-3027
Serial Title: American Mineralogist
Serial Volume: 102
Serial Issue: 6
Title: The spin state of Fe (super 3+) in lower mantle bridgmanite
Affiliation: Universitaet Bayreuth, Bayerisches Geoinstitut, Bayreuth, Germany
Pages: 1263-1269
Published: 201706
Text Language: English
Publisher: Mineralogical Society of America, Washington, DC, United States
References: 60
Accession Number: 2017-052118
Categories: Geophysics of minerals and rocks
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. 1 table
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Abstract, copyright, Mineralogical Society of America. Reference includes data from GeoScienceWorld, Alexandria, VA, United States
Update Code: 201728
Close Modal

or Create an Account

Close Modal
Close Modal