Pressure and temperature dependence of the structure of liquid Sn up to 5.3 GPa and 1373 K

Abstract

ABSTRACTPressure and temperature dependence of the structure of liquid Sn has been measured up to 5.3 GPa and 1373 K using multi-angle energy-dispersive X-ray diffraction in Paris–Edinburgh cell. Under nearly isobar condition at ∼1 GPa, liquid Sn displays a normal behavior with gradual structural changes with temperature up to 1373 K. Under isothermal compressions at 850 and 1373 K, however, the structure factors of liquid Sn both show a turn-over at ∼3 GPa in the height of the first diffraction peak. According to the hard sphere cluster model, the structure of liquid Sn may be viewed as two different types of clusters. Below ∼3 GPa, it is shown that the packing fraction of the dominant cluster (occupying ∼0.94 fraction) changes with compression, while above ∼3 GPa, the packing fractions and the hard sphere diameters of both clusters start to influence the structure, causing significant changes with increasing pressure. Our results suggest that the compression behavior of liquid Sn changes from localized densification only in one cluster below ∼3 GPa to homogeneous structural changes in both clusters above ∼3 GPa.