碳酸铅在不同传压介质下的高压拉曼研究  

High Pressure Raman Spectroscopic Study of PbCO_(3) in Different Pressure Transmitting Medium

作　　者：阿卜力孜·麦提图尔荪 艾尼瓦尔·吾术尔 谢翠焕 亓文明 ABLIZ Matursun;ANWAR Hushur;XIE Cuihuan;QI Wenming(School of Physical Science and Technology,Xinjiang University,Urumqi 830046,Xinjiang,China)

机构地区：[1]新疆大学物理科学与技术学院,新疆乌鲁木齐830046

出　　处：《高压物理学报》2022年第1期35-46,共12页Chinese Journal of High Pressure Physics

基　　金：教育部留学回国人员科研启动基金(60594)。

摘　　要：为研究PbCO_(3)在高压下的稳定性,利用金刚石对顶砧技术,采用NaCl固体、甲醇-乙醇-水混合液体(16∶3∶1)和甲醇-乙醇混合液体(4∶1)做传压介质,开展了PbCO_(3)的高压拉曼实验,最高压强分别达到24.5、25.0和67.0 GPa。研究发现,PbCO_(3)在10、15和30 GPa左右发生相变,在静水压强条件下CO^(2-)_(3)基团的ν^(2-)外弯曲振动模出现了软化现象。通过对比得到不同传压介质中PbCO_(3)的Grüneisen参数γ,发现相变机制略有不同,并且压强对晶格振动的影响CO^(2-)_(3)基团的影响大,这是由Pb^(2+)―O键的键长较大造成的。在所研究的压强范围内,PbCO_(3)没有发生分解或非晶化,30.0 GPa以上出现的PbCO_(3)-Ⅳ相直至67.0 GPa都很稳定。Using diamond anvil cell(DAC)technique and Raman spectroscopy,we have studied the stability of PbCO_(3) at high pressure.Solid NaCl,mixture of methanol-ethanol-water(16∶3∶1)and methanolethanol(4∶1)were used as pressure transmitting medium.The highest pressure in this study reached up to 24.5,25.0 and 67.0 GPa,respectively.It is found that PbCO_(3) undergoes three phase transitions at around 10,15 and 30 GPa,respectively.In addition,the softening of the out of bending vibration mode belonging to CO^(2-)_(3)group was observed.By comparison with the Grüneisen parameters(γ)of PbCO_(3) in different pressuretransfer media,the phase transition mechanism is slightly different,and the influence of pressure on lattice vibration is greater than that of CO^(2-)_(3)group,which is attributed to the larger distance of the Pb^(2+)—O bond.PbCO_(3) did not decompose or amorphized in the pressure range of 67.0 GPa,the highest pressure reached in this study.The observed PbCO_(3)-Ⅳphase above 30.0 GPa is stable up to 67.0 GPa.

关 键 词：PbCO_(3) 拉曼光谱 传压介质 高压 相变 

分 类 号：O521.2[理学—高压高温物理]