Insights on dense silicate melts from shock-compression coupled to in situ X-ray probes

Molten silicates existing at depth play an important role in planetary evolution. Yet, understanding the local structure and properties of liquid silicates under extreme pressure and temperature remains challenging due to the inherent complexities of experimental measurements in such conditions and to the theoretical challenges caused to atomistic simulations by the description of Fe atom behavior. In this presentation, we will show recent results obtained by coupling laser-driven dynamic compression to in situ X-ray probes at the MEC end-station of LCLS at SLAC (Menlo Park, CA, USA) and at the ID24-HPLF instrument at the ESRF (Grenoble, France). The combination of the ultrabright X-ray sources and high-power optical lasers allowed us to probe the local atomic arrangement, spin-state and insights on the electronic structure of shock compressed liquid (Mg,Fe)SiO3 and other Fe-bearing compositions up to 400 GPa along their Hugoniot.