Research at the European XFEL: Water research on spontaneous crystallization

Water is one of the most ubiquitous and vital substances for our survival and is thus also one of the most well-studied samples in fundamental research. E.g. understanding ice nucleation in metastable water is important for many research fields, including cryobiology, astrophysics and atmospheric science.
In this experiment at European XFEL’s SPB/SFX instrument Jonas A. Sellberg from KTH Royal Institute of Technology in Sweden investigates which structural motifs aid or frustrate spontaneous nucleation and subsequent crystal growth. Fluctuation X-ray scattering in combination with sophisticated machine-learning algorithms were used to take a scattering experiment all the way to structural motifs without ad hoc fits or a priori knowledge. Valuable insight about the structure of the growing nucleus have been gained, whether ice grows dendritically or in planar sheets, and whether growth defects can be inferred from local water structure prior to crystallization.