Amazing stuff! At attosecond timescale. "Scientists stop the motion of atoms to watch electrons move in liquid water."
"In an experiment akin to stop-motion photography, scientists have isolated the energetic movement of an electron while “freezing” the motion of the much larger atom it orbits in a sample of liquid water. ...
a new window into the electronic structure of molecules in the liquid phase on a timescale previously unattainable with X-rays. ..."
a new window into the electronic structure of molecules in the liquid phase on a timescale previously unattainable with X-rays. ..."
From the abstract:
"Attosecond-pump/attosecond-probe experiments have long been sought as the most straightforward method to observe electron dynamics in real time. Although numerous successes have been achieved with overlapped near infrared femtosecond and extreme ultraviolet attosecond pulses combined with theory, true attosecond-pump/attosecond-probe experiments have been limited. We used a synchronized attosecond x-ray pulse pair from an x-ray free electron laser to study the electronic response to valence ionization in liquid water via all x-ray attosecond transient absorption spectroscopy (AX-ATAS). Our analysis showed that the AX-ATAS response is confined to the subfemtosecond timescale, eliminating any hydrogen atom motion and demonstrating experimentally that the 1b1 splitting in the x-ray emission spectrum is related to dynamics and is not evidence for two structural motifs in ambient liquid water."
First-ever atomic freeze-frame of liquid water Findings open a whole new field of experimental physics
Attosecond-pump attosecond-probe x-ray spectroscopy of liquid water (no public access)
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