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研究地球深部各圈层的物质组成、结构以及热动力学过程是近些年来地球科学工作者最为重要的任务之一。其中，高温高压条件下对含水矿物脱水过程的实验研究是了解地球深部水含量的一个重要方法。在本次工作中，借助于金刚石压腔结合Solartron?1260阻抗/增益?相位分析仪和拉曼光谱分析仪，在0?24.2 GPa以及293?673 K的条件下原位测量了胆矾脱水前后的电导率和拉曼光谱变化，取得结果如下：1. 在0?23.5 GPa和293 K条件下，原位测量了胆矾的拉曼光谱。胆矾硫酸根振动模和水分子振动模的拉曼平移以及拉曼半高宽分别在7.3和10.3 GPa处存在有两个明显的不连续变化。由此，我们推断胆矾在7.3和10.3 GPa处可能发生两次次级相变。卸压之后，胆矾的拉曼光谱恢复到初始状态，证明由压力引起的相变是可逆的。2. 在0?24.2 GPa和293 K条件下，原位测量了胆矾的电导率。加压过程中，胆矾电导率在7.2和10.2 GPa处存在有两个明显的间断点。这两处压力点与高压拉曼光谱的实验结果相一致，进一步证明了样品在~7.2和~10.2 GPa处发生有两个相变。3. 通过胆矾硫酸根拉曼峰的劈裂和水分子拉曼峰的展宽，我们得到胆矾在2.9和5.8 GPa处的脱水温度分别为353和503 K。卸压之后，胆矾的拉曼峰均显示为三水硫酸铜 (CuSO4?3H2O) 的特征，这表明由于矿物脱水导致的结构相变是不可逆的。4. 根据胆矾升温过程中电导率发生的突然变化，我们得到样品在3.2和6.2 GPa处的脱水温度区间分别为323?353和523?553 K。综合高温高压拉曼光谱和电导率的实验结果，胆矾的脱水温度与压力之间的函数关系被进一步揭示。这种脱水温度与压力之间的正相关性可能是与压力改变了胆矾氢键之间的相互作用有关。

In recent years, the study on the composition, structure, and thermodynamic process in the Earth’s interior has become one of the most important tasks for geoscientists. Systematic investigations on the dehydration process of the hydrous minerals at high temperature and high pressure conditions are crucial to disclose the water content in the Earth’s interior. In the present studies, the in–situ electrical conductivity and Raman spectroscopy measurements were conducted by using a diamond anvil cell in conjunction with Solartron–1260 Impedance/Gain–phase analyzer and a Raman spectrometer (Invia, Renishaw). The experimental results are indicated as follows:Under the experimental conditions of 0?23.5 GPa and 293 K, the in–situ Raman scattering measurements were performed. Two secondary phase transitions were determined by virtue of the obvious discontinuities at 7.3 and 10.3 GPa in the Raman shifts and full width at half maximum for the vibrational modes of sulfate anion and water molecules. Upon decompression, the Raman spectrum recovered to the original state, which indicated that the phase transitions were reversible. Under the experimental conditions of 0?24.2 GPa and 293 K, the in–situ electrical conductivity measurements were conducted. Tow phase transitions were further confirmed at 7.2 and 10.2 GPa, respectively, according to the discontinuous changes of the electrical conductivity with pressure.Based on the splitting and broadening of the vibrational modes for sulfate anions and water molecules, the dehydration temperatures of chalcanthite were determined at 353 and 503 K at respective 2.9 and 5.8 GPa. Upon decompression, the Raman spectrum for recovered sample was characterized as the bonattite (CuSO4?3H2O), which suggested that this structural phase transition was irreversible.By virtue of the abrupt changes in the electrical conductivity, the dehydration temperatures of chalcanthite were obtained at 323?353 and 523?553 K correspondingly at 3.2 and 6.2 GPa, respectively. Furthermore, a positive relationship between dehydration temperature and pressure was established, which is caused by the pressure?dependent interaction of hydrogen bonding for water molecules.