Density measurements of liquid Fe‐S alloys at high‐pressure

We present the first static measurements of the density of metallic liquids in the Fe‐S system in the pressure and temperature range 1.5 GPa–6.2 GPa and 1500 K–1780 K. Density is inferred from X‐ray absorption experiments carried out with a large volume press at the European Synchrotron Radiation Facility. It is shown that increasing the amount of sulfur in liquid iron decreases the bulk incompressibility by −2.5 GPa per 1 weight% of S. These data are important for constraining the presence and amount of sulfur in the cores of small planetary bodies.