Investigation into high-pressure behavior of MnTiO_3:X-ray diffraction and Raman spectroscopy with diamond anvil cells

作     者：Xiang Wu Shan Qin Leonid Dubrovinsky 

作者机构：Key Laboratory of Orogenic Belts and Crustal Evolution MOE ＆ School of Earth and Space Sciences Peking University Beijing 100871 China Bayerisches Geoinstitut Universita＇t Bayreuth Bayreuth D-95440 Germany 

出 版 物：《Geoscience Frontiers》 (地学前缘（英文版）)

年 卷 期：2011年第2卷第1期

页      面：107-114页

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 0708[理学-地球物理学] 080501[工学-材料物理与化学] 070302[理学-分析化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 0704[理学-天文学] 

基　　金：an Alexander von Humboldt Fellowship in Germany and S.Qin acknowledges the financial support of the National Natural Science Foundation of China(Grant No. 40972029) 

主　　题：MnTiO3 Ilmenite Lithium niobate Perovskite Phase transition Equation of state 

摘      要：The structural stability of manganese titanate MnTiO3 at high pressure was investigated by X-ray diffraction and Raman spectroscopy with diamond anvil cells. Ilmenite-type MnTiO3 is stable at least to 26.6 GPa, and lithium niobate type MnTiO3 reversibly transforms at room temperature to perovskite at 2.0 GPa. Bulk moduli （K300） of ilmenite, lithium niobate and perovskite are 174（4） GPa, 179 （8） GPa, and 208（5） GPa, respectively （at fixed first pressure derivative K＇ = 4）. The Griineisen parameter T has been estimated to be 1.28 for ilmenite and 1.75 for perovskite. In ilmenite phase, TiO6 octahedra become more regular with increasing pressure. In perovskite phase structural distortion increases with pressure increase.