Spin state of ferric iron in MgSiO3 perovskite and its effect on elastic properties

Computer Science

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

13

Scientific paper

Recent studies have indicated that a significant amount of iron in MgSiO3 perovskite (Pv) is Fe3+ (Fe3+/ΣFe = 10-60%) due to crystal chemistry effects at high pressure (P) and that Fe3+ is more likely than Fe2+ to undergo a high-spin (HS) to low-spin (LS) transition in Pv in the mantle. We have measured synchrotron Mössbauer spectroscopy (SMS), X-ray emission spectroscopy (XES), and X-ray diffraction (XRD) of Pv with all iron in Fe3+ in the laser-heated diamond-anvil cell to over 100 GPa. Fe3+ increases the anisotropy of the Pv unit cell, whereas Fe2+ decreases it. In Pv synthesized above 50 GPa, Fe3+ enters into both the dodecahedral (A) and octahedral (B) sites approximately equally, suggesting charge coupled substitution. Combining SMS and XES, we found that the LS population in the B site gradually increases with pressure up to 50-60 GPa where all Fe3+ in the B site becomes LS, while Fe3+ in the A site remains HS to at least 136 GPa. Fe3+ makes Pv more compressible than Mg-endmember below 50 GPa because of the gradual spin transition in the B site together with lattice compression. The completion of the spin transition at 50-60 GPa increases bulk modulus with no associated change in density. This elasticity change can be a useful seismic probe for investigating compositional heterogeneities associated with Fe3+.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Spin state of ferric iron in MgSiO3 perovskite and its effect on elastic properties does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Spin state of ferric iron in MgSiO3 perovskite and its effect on elastic properties, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spin state of ferric iron in MgSiO3 perovskite and its effect on elastic properties will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1443233

All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.