Review: X-ray scattering methods with synchrotron radiation
Resonant X-ray excitation (purple) core excites the oxygen atom within a H2O molecule. This causes ultrafast proton dynamics. The electronic ground state potential surface (bottom) and the bond dynamics is captured by distinct spectral features in resonant inelastic X-ray scattering (right).
© Martin Künsting /HZB
Synchrotron light sources provide brilliant light with a focus on the X-ray region and have enormously expanded the possibilities for characterising materials. In the Reviews of Modern Physics, an international team now gives an overview of elastic and inelastic X-ray scattering processes, explains the theoretical background and sheds light on what insights these methods provide in physics, chemistry as well as bio- and energy related themes.
"X-ray scattering can be used to investigate and resolve a wide variety of issues from the properties and excitations of fuctional solids, to homogeneous and heterogeneous chemical processes and reactions or even the proton pathway during the splitting of water," explains Prof. Dr. Alexander Föhlisch, who heads the Institute Methods and Instrumentation for Research with Synchrotron Radiation at HZB.
The article gives an overview of experimental and theoretical results in the field of resonant scattering of tunable soft and hard X-rays. The focus is on resonant inelastic X-ray scattering (RIXS) and resonant Auger scattering (RAS). In the review, the authors outline the most important achievements from the last two decades at Synchrotrons up to the latest advances in time-resolved studies with X-ray free-electron lasers.
- Electrocatalysis with dual functionality – an overviewHybrid electrocatalysts can produce green hydrogen, for example, and valuable organic compounds simultaneously. This promises economically viable applications. However, the complex catalytic reactions involved in producing organic compounds are not yet fully understood. Modern X-ray methods at synchrotron sources such as BESSY II, enable catalyst materials and the reactions occurring on their surfaces to be analysed in real time, in situ and under real operating conditions. This provides insights that can be used for targeted optimisation. A team has now published an overview of the current state of knowledge in Nature Reviews Chemistry.
- Successful master's degree in IR thermography on solar facadesWe are delighted to congratulate our student employee Luca Raschke on successfully completing her Master's degree in Renewable Energies at the Hochschule für Technik und Wirtschaft Berlin - and with distinction!
- BESSY II: Phosphorus chains – a 1D material with 1D electronic propertiesFor the first time, a team at BESSY II has succeeded in demonstrating the one-dimensional electronic properties in phosphorus. The samples consisted of short chains of phosphorus atoms that self-organise at specific angles on a silver substrate. Through sophisticated analysis, the team was able to disentangle the contributions of these differently aligned chains. This revealed that the electronic properties of each chain are indeed one-dimensional. Calculations predict an exciting phase transition to be expected as soon as these chains are more closely packed. While material consisting of individual chains with longer distances is semiconducting, a very dense chain structure would be metallic.