金刚烷的高压拉曼光谱研究

Raman Scattering Investigations of Adamantane under High Pressure

对金刚烷(C10H16)进行了常温原位高压拉曼光谱研究,最高压力为25 GPa。通过分析高压拉曼光谱,结合拉曼频移随压力的变化情况,得出在实验压力范围内C10H16发生了多次相变。0.6 GPa时,C10H16由常温常压下的无序相(α相)转变为有序相(β相);继续加压至1.7 GPa时,第2次结构相变开始,直至3.2 GPa,第2次相变完全结束;第3次相变开始于6.3 GPa,结束于7.7 GPa;22.9 GPa时发生了第4次结构相变。另外,首次在拉曼光谱上探测到第3次相变过程中晶格振动峰的变化,说明第3次相变并非前人报道的等结构相变。

Results of Raman scattering measurements under pressure up to 25 GPa on adamantane(C10H16)carried out at room temperature are reported. The analysis of Raman data indicated four phase transitions.The ambient pressure disordered Fm3 m structure(α-C10H16) transformed to a high pressure ordered phase at 0.6 GPa. Continue to pressurize to 1.7 GPa, the second structure phase transition began, and completely accomplished until 3.2 GPa. The third transition began at 6.3 GPa, ended at 7.7 GPa. C10 H16 transformed to a new phase at 22.9 GPa. Because of the new lattice peak occurred during the third transition, it was defined to a first-order transition.