The humite-group minerals could be potential water carriers as the dehydration products of serpentine in subduction slabs. Fluorine is an important element incorporated into the crystal structures through the substitution mechanism of OH⁻ = F⁻, and has significant impacts on the thermodynamic properties. We conducted in situ high-pressure Raman and Fourier transform infrared (FTIR) measurements on natural F-bearing clinohumite, humite and norbergite samples, up to approximately 19GPa. The isothermal mode Grüneisen and intrinsic anharmonic parameters were calculated for both the lattice and OH-stretching modes, and the anharmonic contribution to the heat capacities was further evaluated for these hydrous phases. As compared with the OH-clinohumite sample, the anharmonic contribution is larger in magnitude for the F-bearing clinohumite, while such anharmonic contributions are even more significant in the humite and norbergite samples with higher fluorine concentrations. Both the Raman and FTIR spectra indicate that the OH-stretching modes above 3450 cm⁻¹, which are controlled by the neighboring HH, systematically show positive pressure dependences. On the other hand, the OH bands below 3450 cm⁻¹ shift to lower frequencies at elevated pressure, due to F⁻ or Ti⁴⁺ substitutions. The F⁻ substitution of OH⁻ group could alleviate local HH repulsion effect, and create new H sites with shorter hydrogen bond lengths. These hydrogen bond would get shorter (negative pressure dependences), and are likely to participate in the hydrogen bond symmetrization at high pressure.

作为俯冲板中蛇纹石的脱水产物，腐殖质类矿物可能是潜在的水载体。氟是通过OH的取代机制引入晶体结构的一个重要因素^-  = F ^-，并且对热力学性质有重大影响。我们对含氟的斜长石，腐殖土和钠长石样品（最高约19GPa）进行了原位高压拉曼和傅里叶变换红外（FTIR）测量。计算了晶格和OH拉伸模式的等温模式Grüneisen和本征非谐参数，并进一步评估了这些水相的非谐对热容的影响。与OH斜发石样品相比，含F斜长石的非谐贡献更大，而氟含量较高的腐殖质和钠长石样品的非谐贡献更大。拉曼光谱和FTIR光谱均表明3450 cm ^-1以上的OH拉伸模式由相邻的H H控制的，系统地显示出正压力依赖性。在另一方面，下面3450厘米的OH频带^-1移位到在升高的压力较低的频率时，由于到F ^-或Ti ⁴⁺替代。在F ^- OH的取代^-组能减轻为本地H ħ排斥效果，并创建具有较短的氢键长度新的H点。这些氢键将变得更短（负压依赖性），并且可能在高压下参与氢键对称化。