X‐ray Compton scattering measurements using synchrotron radiation are carried out for liquid sodium (Na) from 473 K up to 1273 K. Utilizing the liquid state allows us to realize a continuous density reduction by controlling temperature and pressure. Valence Compton profiles (CPs) clearly exhibit thermodynamic state dependence as the temperature increases. Experimental CPs, CP differences, and electron kinetic energy are compared with those of the electron gas model. Combined with the analysis using the Fourier‐transformed CPs, the observed behaviors can be reasonably explained by the reduction in the electron density with volume expansion of the liquid.

中文翻译：

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高温下液态钠的X射线康普顿散射研究

对于从473 K到1273 K的液态钠（Na），使用同步加速器辐射进行X射线康普顿散射测量。利用液态，我们可以通过控制温度和压力来实现密度的连续降低。价康普顿分布（CP）随温度升高而清楚地显示出热力学状态依赖性。将实验CP，CP差和电子动能与电子气模型的CP进行比较。结合使用傅里叶变换CP进行的分析，观察到的行为可以合理地解释为电子密度随液体体积膨胀而降低。