HPC-Europa3 visitor publishes paper in Physical Review Letters

1 March 2019

Former HPC-Europa3 visitor Dr Mats Simmermacher, Dr Adam Kirrander (Mats' host from the University of Edinburgh's School of Chemistry), and their collaborators from Edinburgh and Copenhagen have recently published a paper in the prestigious Physical Review Letters where they discuss a new effect in ultrafast X-ray scattering. 

Mats is currently Lecturer in Chemical Physics (fixed-term) in the School of Chemistry. He enjoyed his time as a HPC-Europa3 visitor so much that he applied for a job here in Edinburgh. Mats is covering for his former host Dr Kirrander during a sabbatical, he is currently teaching Chemistry and Chemical Physics students in Quantum Chemistry and Quantum Dynamics.

The paper "Electronic Coherence in Ultrafast X-Ray Scattering from Molecular Wave Packets" is based on simulations Mats that ran on ARCHER and proposes a novel type of experiment that utilises the extremely short and intense X-ray pulses produced by Free-Electron Lasers (XFELs) to track the motion of atomic nuclei and electrons in molecules. In this experiment the X-rays are scattered by the molecule onto a detector. By analysis of the resulting scattering patterns that are measued at different points in time, information about the structural evolution of the molecule can be obtained.

The authors show how a quantum mechanical effect known as electronic coherence could affect the experimental signal and discuss how an interference of different electronic states of the molecule becomes visible in the simulated scattering patterns. This interference provides additional insight that goes beyond the mere structural information and may help physicists and chemists to understand whathappens to a molecule after photoexcitation or in a chemical reaction.

You can find the paper here: https://doi.org/10.1103/PhysRevLett.122.073003