【摘要】 本文对TiO₂的同质多象变体:金红石、锐钛矿、板钛矿和铌铁矿结构型TiO₂-Ⅱ分别进行了群论分析,并对实测拉曼光谱进行了归属讨论,金红石和锐钛矿的拉曼光谱研究表明,在高压条件下,两者都表现出相变特征。金红石在压力为102kbar时转变为铌钛矿型TiO₂-Ⅱ,而锐钛矿在压力为54kbar时转变为TiO₂-Ⅱ,并且前者的相变是缓慢的过程,而后者是瞬时转变,本文的研究还显示,金红石、锐钛矿和TiO2-Ⅱ的拉曼谱带的频率和压力之间具有线性相关关系,其中每一个变体都有一个谱带与压力成负相关关系。更多还原

【Abstract】 In this paper, the TiO₂ polymorphs: rutile, anatase, brookite and columbite-type TiO₂-Ⅱ were analysed respectively according to the group theories, and the Raman spectra of these phases measured at ambient conditions were discussed for their assigment. The Raman spectroscopic studies showed transitions at high pressures for both futile and anatase. Rutile transforms to a columbite-type TiO₂-Ⅱ at 102 Kbar, and the transition is sluggish. Anatase transforms to the same phase at 54 Kbar, but the transition is instantaneous. It is also reported that the Raman bands were recorded as a function of pressure for the TiO₂ polymorphs. Each of these phases has one band, of which the frequency decreasees with increasing pressure.更多还原