四氯化钛的压致相变研究

PRESSURE INDUCED PHASE TRANSITION IN TITANIUM TETRACHLORIDE

李风雷

11649049

硕士

物理学

王善民

2018-05-30

2018-07-04

哈尔滨工业大学

深圳

四氯化钛是钛以及钛白粉生产中最重要的中间物，对其性质结构的研究在钛工业中有着非常重要的意义。同时四氯化钛是少有的在常温常压条件下为无色液态的化合物，对其结构性质等的研究有利于理解过渡金属氯化物这一类物质的特质。高压 科学是一门新兴的交叉学科，利用高压实验研究材料在极端条件下的理化性质是科学研究的热点方向。本文将金刚石对顶砧设备与红外光谱、拉曼光谱以及X 射线衍射技术相结合，对四氯化钛的压致相变现象进行了详细的研究。首先通过同步辐射 X 射线衍射，发现了四氯化钛在 5 GPa 和 10 GPa 左右存在着相变，且利用 Rietveld方法对其结构进行了精修，得出在 4.1 GPa 附近为三斜结构中的 P 1 空间群，在 8.3 GPa 附近为单斜结构中的 P2/M 空间群，在 18.7 GPa 附近为单斜结构中的 P2/A 空间群。之后利用高压原位红外光谱实验以及高压原位拉曼光谱实验进一步对结果进行了验证。另外从拉曼光谱以及对样品颜色的观测中，可以得出四氯化钛在 1.5 GPa 左右发生了固化且在 5 GPa 和 10 GPa 处存在压致相变现象。以上实验表明四氯化钛的压致相变过程为可逆相变，且存在滞后现象。本文首次观测到了四氯化钛的压致相变现象，对四氯化钛的工业应用以及过渡金属氯化物的结构相变研究都具有重要指导作用。

Titanium tetrachloride is the most important intermediate in the production of titanium and titanium dioxide. The study of its structure and p roperties has very important significance in the titanium industry. At the same time, titanium tetrachloride is a rare compound that is a colorless liquid under normal temperature and pressure conditions, and the study of its structural and properties is useful to understanding of the characteristics of transition metal chlorides. High pressure science is a new interdisciplinary discipline. The use of high pressure experiments to study the physical and chemical properties of materials under extreme conditions is a hot topic of scientific research.In this paper, the diamond anvil cell is combined with infrared spectroscopy, Raman spectroscopy and X ray diffraction techniques to study the pressure induced phase trans i tion of titanium tetrachloride. Firstly, the X ray diffraction of synchrotron radiation shows that TiCl 4 has pressure induced phase transition s around 5 GPa and 10 GPa, and its str ucture is refined by the Rietveld method. It is found that it is a triclinic structure with the P 1 space group near 4.1 GPa. and a monoclinic structure with P2/M near 8.3 GPa, and a P2/A space group in a monoclinic structure near 18.7 GPa. Then the high p ressure in situ infrared spectroscopy experiment and the high pressure in situ Raman spectroscopy experiment were used to further verify the results. In addition, from Raman spectroscopy and the observation of the color of the sample, it can be concluded t hat titanium tetrachloride has been solidified around 1.5 GPa and that pressure induced phase transitions have occurred at 5 GPa and 10 GPa. The above experiments show that the pressure induced phase transition of titanium tetrachloride is a reversible pha se change and there is a hysteresis phenomenon.In this paper, the phenomenon of pressure induced phase transition of titanium tetrachloride is observed for the first time. It has important guiding role in the industrial application of titanium tetrachlori de and the structural phase transition of transition metal chlorides.

四氯化钛 金刚石对顶砧 红外光谱 拉曼光谱 同步辐射 相变

titanium tetrachloride diamond anvil cell infrared spectroscopy raman spectroscopy synchrotron radiation phase transition

中文

联合培养

哈尔滨工业大学

李风雷. 四氯化钛的压致相变研究[D]. 深圳. 哈尔滨工业大学,2018.