【摘要】 利用金刚石对顶砧（DAC）装置产生高压,在室温下、0～32 GPa压力范围,对天青石（SrSO₄）进行了原位高压X射线衍射和拉曼光谱研究.根据高压X射线衍射的数据,测定了天青石的等温状态方程,得到天青石的零压体弹模量K_To=83GPa（K′_To=4）,在所研究压力范围内没有观察到相变的发生.高压拉曼光谱的数据显示,在5GPa左右,SO₄四面体弯曲振动峰发生劈裂,这是由SO₄四面体畸变引起的;同时,所有的拉曼振动峰都随着压力的增加而增加,并且,高频模的平均压力导数要高于低频模的,根据以上数据获得了模格林奈森参数.更多还原

【Abstract】 The in-situ angle dispersive X-ray powder diffraction and Raman spectroscopy of celestite has been measured under high pressure（0～32 GPa）conditions with diamond anvil cell（DAC）.Based on the X-ray data,we obtained the equation of state of celestite,the bulk modulus K_T0is 83 GPa(K’_T0=4). We have not found any convincing evidence for a phase transformation in the experimental pressure range.Raman spectrum data display,at pressure about 5GPa,the 628cm^-1peak,bending vibration of the SO₄ tetrahedra,split into two peaks.This results from the lattice distortion of the SO₄ tetrahedra. All the Raman frequencies continuously increase with the increasing pressure.The average pressure derivative of the high frequency modes is larger than that of the low frequency.Based on the above data, the mode Grüneisen parameters for celestite are obtained.更多还原