The amount and distribution of water in nominally anhydrous minerals (NAMs) are usually determined by Fourier-transform infrared spectroscopy. This method is limited by the spot size of the beam to the study of samples with dimensions greater than a few micrometers. Here, we demonstrate the potential of using photoinduced force microscopy for the measurement of water in NAMs with samples sizes down to the nanometer scale with a study of water concentration across grain boundaries in forsterite. This development will enable the study of water speciation and diffusion in small-grained rock matrixes and allow a determination of the influence of nanoscale heterogeneity on the incorporation of water to NAMs.

中文翻译：

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确定纳米级名义上无水矿物的水分含量

通常通过傅立叶变换红外光谱法确定标称无水矿物（NAM）中水的含量和分布。该方法受光束光斑尺寸的限制，只能用于研究尺寸大于几微米的样品。在这里，我们通过研究镁橄榄石中晶界上的水浓度，证明了使用光致力显微镜在NAM中测量水的潜力，样品尺寸低至纳米级。这一进展将使人们能够研究小颗粒岩石基质中水的形态和扩散，并能够确定纳米级异质性对水向NAM掺入的影响。