Properties of Fe-bearing geomaterials at conditions close to the core-mantle boundary

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Structural and electronic properties of rock forming minerals studied at in situ conditions are the key to understand processes inside the Earth including chemistry and dynamics at the core-mantle boundary and core formation. In this project we use X-ray emission spectroscopy to learn about the electronic state and X-ray diffraction to determine the corresponding atomic structure of material at conditions of the core-mantle boundary. We aim also to pioneer the application of new methods at these conditions like valence-to-core emission and X-ray Raman scattering. Latter has the potential to add structural information also for light elements. To reach and densely cover the p-T space of up to 400 GPa and several 1000 K, we apply X-ray heating of material compressed in diamond anvil cells as well as dynamic laser compression techniques. We make use of a new experimental facility, the High-Energy Density Science instrument at the European XFEL GmbH. In the first part of this project, we will focus on solid material and apply static compression techniques. In the second phase we aim at investigating molten material and will apply dynamic compression techniques that have the potential of reaching highest achievable pressures and temperatures in the laboratory. We will focus our study on solid solutions of FeO and MgO, namely on (MgxFe1-xO) with x around 0.8 as this mineral is assumed to be the second-most abundant mineral phase of the lower mantle of the Earth.