Investigating ultrafast structural dynamics using high repetition rate x-ray FEL radiation at European XFEL

European XFEL is an international facility providing hard and soft x-ray free-electron laser radiation for user experiments with a wide range of scientific applications. Its superconducting linear accelerator enables high repetition rate experiments with a broad range of x-ray pulse delivery patterns. The combination of time-resolved experiments, providing access to the time-domain from sub-femtoseconds to milliseconds, with atomic resolution x-ray geometric and electronic structure determination methods is responsible for the bulk of scientific applications of European XFEL. In addition, the extreme x-ray intensities and coherence properties open new methods for studying matter out of equilibrium. After start of operation in 2017, the facility now harvests scientific applications with impact to the challenge areas climate and energy, health, environment and sustainability, and digitalization. Extensions of European XFEL aim to increase performance and capabilities for new scientific applications. An upgrade of the facility in the early 2030s will increase the applicability of European XFEL to solid materials and provide dedicated instruments for improved conditions in specific research fields.