Meeting room "Glova", 4 floor, Integrated Research Building
Abstract
It is now widely recognized that pressure-induced spin transitions of iron in the lower mantle minerals largely affect the structures and physical properties of those minerals, the iron partitioning among those minerals, and thereby the dynamics of the lower mantle. However, the spin transitions of iron in Mg-perovskite (MgPv) and post-Mg-perovskite (PMgPv) are still unclear. Recently, we measured the spin states of ferric iron in Al-bearing MgPv and PMgPv up to 200 GPa and 165 GPa, respectively, by X-ray emission spectroscopy at room temperature using the well qualified samples. The obtained results indicate that the cation exchange reaction of ferric iron and Al between the A-site and B-site plays an important role on the spin transitions of ferric iron in MgPv and PMgPv. In my talk, I will introduce our results on the spin transitions of ferric iron in MgPv and PMgPv, and then talk about their implications to the lower mantle. In the former part of my talk, I will give some introductory talk on the "crystal field splitting" and "pressure-induced spin transition of iron", since this seminar holds concurrently the lecture for the graduate-course students.
For inquiry：Taku Tsuchiya TEL:（089）927-8198
E-mail takut@sci.ehime-u.ac.jp
