常温和压力0．1～1300MPa下硬石膏的拉曼光谱研究

RESEARCH ON RAMAN SPECTRA OF ANHYDRITE AT PRESSURE OF 0.1-1300 MPa AND ROOM TEMPERATURE

利用立方氧化锆压腔装置测量了高压下硬石膏中硫酸根离子内部S-O键的四个振动(对称伸缩振动、弯曲振动、反对称伸缩振动和变形弯曲振动)的拉曼位移,研究结果表明:在25 ℃和0.1～1 300 MPa压力范围内硬石膏未发生相变,所观察到的硬石膏各个拉曼峰的位移值随压力的增加而线性增加,它们与压力之间的关系可分别表达为:ν1018=0.0053 p+1016.8,ν417=0.0013p+416.82,ν498=0.0044 p+499.25,ν1129=0.0052p+1128.5,ν1160=0.0067 p+1159.5, ν608=0.0028 p+608.76, ν627=0.0036 p+627.01, ν675=0.0039 p+675.32,且伸缩振动受压力的影响比弯曲振动大.其1018 cm-1峰强度大,是石英464 cm-1峰的6倍,因此硬石膏也是宝石压腔良好的压力标定物质.

This paper measured the Raman peak displacements of the four vibration modes of S-O bonding of anhydrite at high pressures using a cubic zirconia anvil cell. The research results showed that anhydrite didn＇t undergo phase transition at the temperature of 25℃ and the pressure of 0.1-1300MPa. The Raman peak positions of S-O bonding of anhydrite shift toward high wave numbers with increasing system pressure, and the relations between the peak positions and the system pressure are given as follows： υ1018=0.0053p ＋ 1016.8, υ417=0.0013p ＋ 416.82, υ498 =0.0044p ＋ 499.25, υ1129 =0.0052p ＋ 1128.5, υ1160 = 0.0067p ＋ 1159.5, υ608 =0.0028p ＋ 608.76, υ627=0.0036p＋627.01, υ675=0.0039p ＋ 675.32, stretching vibrations are more affected by pressure than bending vibrations. Besides the intensity of its 1018cm^-1 Raman peak is five times greater than that of 464cm^-1 Raman peak of quartz, anhydrite is also reliable as a pressure gauge.