I will report on in situ X-ray probing of laser-driven shock waves at megabar pressures. At X-ray Free Electron Lasers, simultaneous use of spectrally resolved X-ray scattering, X-ray diffraction and optical diagnostics such as VISAR and SOP provides precise insights into the dynamics of chemical processes at these extreme conditions. At European XFEL, the DiPOLE laser with its repetition rate of up to 10 Hz now allows for measurements of unprecedented precision and enables photon-hungry spectroscopic techniques that were so far unreachable in dynamic compression experiments. The first experimental campaigns exploiting these capabilities provide insights into chemical kinetics at extreme conditions, the formation of peculiar bonding and material structures, and the presence of liquid metallic hydrogen in mixtures of light elements. These results inform models for planetary interiors, provide the pathway to the synthesis of new materials via extreme conditions, and may be crucial for designing efficient ablator materials for IFE. I will also give an outlook on a new campaign at the National Ignition Facility to explore the use of dynamic chemistry around 10 Mbar to synthesize new materials such as the so far only predicted BC-8 structure of carbon.
 

Warm Dense Matter,Planetary interiors,Inertial fusion