Recently we are witnessing the boom of high-pressure science and technology from a small niche field to becoming a major dimension in physical sciences. One of the most important technological advances is the integration of synchrotron nanotechnology with the minute samples at ultrahigh pressures. Applications of high pressure have greatly enhanced our understanding of the electronic, phonon, and doping effects on the newly emerged graphene and related 2D layered materials. High pressure has created exotic stoichiometry even in common Group 17, 15, and 14 compounds and drastically altered the basic s and p bonding of organic compounds. Differential pressure measurements enable us to study the rheology and flow of mantle minerals in solid state, thus quantitatively constraining the geodynamics. They also introduce a new approach to understand defect and plastic deformations of nano particles. These examples open new frontiers of high-pressure research.

本文以金红石单晶TiO2和锐钛矿多晶TiO2为研究对象, 应用金刚石小压机和原位拉曼光谱测量技术, 系统研究了室温高压下TiO2的结构相变。原位拉曼测量表明, 金红石单晶TiO2在压力达到12.91 GPa时开始发生由金红石结构向斜锆石结构(MI)的相变, 当压力达到14.16 GPa时, 相变完成; 继续加压到21.65 GPa, 没有发现进一步的相变; 卸压时由斜锆石结构转变为PbO2结构, 相变发生在大约7.11 GPa处。锐钛矿多晶TiO2在压力达到4.26 GPa时开始向PbO2结构转变, 当压力达到8.34 GPa时相变完成; 继续加压到12.94 GPa, 样品开始发生由PbO2结构向斜锆石结构的相变, 当压力达到18.74 GPa时相变完成; 继续加压到21.39 GPa, 没有发现进一步的相变; 卸压时也由斜锆石结构转变为PbO2结构, 起始相变压力点应高于8 GPa。