日時 ： ２００９年１１月６日（金）※16：30～
場所 ： 愛媛大学総合研究棟Ⅰ 4F 共通会議室（理学部構内）
要 旨
High-pressure behavior of Fe2O3, an important end-member compound for characterizing properties of ferric iron in the Earth’s mantle, has been of long-standing interest to geophysics. Recently Ono et al. (2005) and Ito et al. (2009) suggested that hematite (a low-pressure polymorph of Fe2O3) transforms to Rh2O3 (II)-type or perovskite structure. But phase boundaries between hematite and the high-pressure phase suggested in the studies are inconsistent with each other. On the other hand, Liu et al. (2002) suggested that hematite transforms to another orthorhombic structure at 22 GPa and ~ 3500 K. So, the phase relation in Fe2O3 at high-pressure and temperature has not been well clarified yet. An equation of state of hematite has been extensively investigated. However these studies were conducted at only 300 K and effect of temperature on the equation of state has been unknown. We carried out in-situ X-ray diffraction experiments at the synchrotron facility SPring-8 using a Kawai-type apparatus to determine the phase relation and the equation of state of Fe2O3 up to 31 GPa at temperature of 1300 K.
問い合わせ先：土屋 卓久 TEL （089）927-8198
E-mail takut@sci.ehime-u.ac.jp
