2012 年 22 巻 2 号 p. 164-169
Pressure range of in situ x-ray observation has been extended very close to 100 GPa, by interfacing the Kawai-type multi-anvil apparatus (KMA) equipped with sintered diamond anvils with the synchrotron radiation at SPring-8. High-pressure phase equilibria in Fe2O3 and MgGeO3 are summarized. Isostructural reduction in electrical resistance of hematite by three orders of magnitude at pressures 54-56 GPa strongly suggests the occurrence of a Mott transition. In MgGeO3, special attention was paid to the dP/dT slope of the phase boundary between perovskite and post-perovskite phases. Spin transition of Fe2+ in (Mg0.83Fe0.17)O is also briefly reported.