Theorists explain how X-ray measurement freezes hydrogen motion, with implications on other areas of chemistry
An international team has performed an attosecond-scale experiment at an X-ray free-electron laser on liquid water for the first time, and the results may change our interpretation of water’s behaviour. The experiment team, led by scientist Linda Young from Argonne National Laboratory in the US, found an unusual signal when they examined liquid water using X-ray flashes that were timed a few hundred attoseconds (an attosecond is a billionth of a billionth of a second). A theory team led by Robin Santra, lead scientist at the research centre DESY and a professor at Universität Hamburg in Germany, and Xiaosong Li, a professor at the University of Washington in the US, used quantum-mechanical techniques for the analysis. Based on the data of the new experiment, they found that a longstanding measurement of the structure of liquid water has been misinterpreted. The effects of this finding not only demonstrate the potential of attosecond research on condensed matter at X-ray lasers, which is so far unprecedented, but also may require a rethink on how a wide range of molecules beyond water, especially organic ones, are structured. The findings have been published in the journal Science.
DESY’s experience and techniques were crucial in this result and form a cornerstone towards the future Centre for Molecular Water Science (CMWS) that DESY is setting up. The experimental and theoretical teams for this result comprise scientists from Argonne National Laboratory, the University of Washington, Pacific Northwest National Laboratory, Washington State University, the University of Chicago, and SLAC National Accelerator Laboratory, all in the US; and DESY, Universität Hamburg, and the Hamburg Cluster of Excellence “CUI: Advanced Imaging of Matter,” all in Germany.
Read more on DESY website
Image: Georgi Dakovski operating the LCLS ChemRIXS beamline, where the experiment was carried out during the pandemic
Credit: Linda Young