High-pressure decomposition of FeTiO₃ perovskite: phase relations up to 35 GPa at high temperature

Abstract

High-pressure phase transition in FeTiO₃ was examined at pressure to 35 GPa and temperature to 1600 oC using a multianvil apparatus. The results indicated that at about 28 GPa FeTiO₃ perovskite dissociates into the mixture of calcium-titanate type Fe2TiO4 and O1 type TiO₂at temperature below 1200 oC, and into the mixture of calcium-titanate type Fe₂TiO₄ and FeTi₂O₅ phase above 1200 oC. These results are different from previous studies performed by laser-heated DAC. We disccuss on the difference of phase relations along with the fact that titanate perovskites do not transform to post-perrovskite but dissociate into two phases.