We know that water is important for life and is involved in almost all processes of importance for the society but it is also unique with many unusual properties. Here we use in particular x-rays to address the structure and dynamics of the hydrogen-bonding network that gives rise to all the unique properties of water. The focus is to follow how the structure and dynamics affected by temperature, pressure and by perturbation through interaction with solutes and interfaces. Another area is to understand water at very cold temperatures and if it can exists as two liquids similar to the two forms of glasses.

The development of x-ray lasers providing intense single x-ray pulses that are a few femtoseconds long in time and are almost fully coherent opens up the field of ultrafast chemistry in a new unique way. This allows for a new paradigm in studies of surface catalytic reactions in real time using optical pump and x-ray spectroscopic probe. The focus is to detect various transient intermediates and the transition state regions but also the energy transfer between the molecules on the surface and the substrate. The overall goal is to provide a fundamental understanding of chemical reactivity of importance for catalysis.

The world faces many challenges over the next few decades concerning energy production, energy storage, and reduced energy impact on the environment. Nearly all of the chemical processes involved in energy conversion utilize catalytic chemical transformations at interfaces between solids and liquids or gases. These include novel electro- or photo-catalytic processes to produce hydrogen and to convert emitted CO2 to fuels, more efficient and stable fuel cell catalysts and selective thermal heterogeneous catalytic processes for generation of methanol, ammonia, higher alcohols and hydrocarbons. Here we use x-rays to probe catalytic surfaces under operational conditions at high gas pressures or at solid-liquid interfaces to detect intermediates and rearrangement of catalytic material itself. From a functional understanding of the involved elementary reaction steps, bonding of intermediates, activation barriers, interfacial charge transfer and restructuring of the catalyst itself, we can envision a rational design of active sites that would catalyze a specific chemical transformation.