Opportunities for Chemistry at the SwissFEL X-ray Free Electron Laser

Abstract

X-ray techniques have long been applied to chemical research, ranging from powder diffraction tools to analyse material structure to X-ray fluorescence measurements for sample composition. The development of high-brightness, accelerator-based X-ray sources has allowed chemists to use similar techniques but on more demanding samples and using more photon-hungry methods. X-ray Free Electron Lasers (XFELs) are the latest in the development of these large-scale user facilities, opening up new avenues of research and the possibility of more advanced applications for a range of research. The SwissFEL XFEL project at the Paul Scherrer Institute will begin user operation in the hard X-ray (2.1-12.4 keV) photon energy range in 2018 with soft X-ray (240-1930 eV) user operation to follow and here we will present the details of this project, it's operating capabilities, and some aspects of the experimental stations that will be particularly attractive for chemistry research. SwissFEL is a revolutionary new machine that will complement and extend the time-resolved chemistry efforts in the Swiss research community.

Perspective: Opportunities for ultrafast science at SwissFEL

“…The hard X-ray branch of SwissFEL consists of three beamlines delivering the FEL radiation into separate experimental hutches 75 . The initial phase of operation will cover the first two experimental hutches, with the third planned for installation in the coming years.…”

Influence of pump laser fluence on ultrafast structural changes in myoglobin

“…The TR-SFX experiment was performed in March (beamtime 1)/May (beamtime 2) 2019 using the Alvra Prime instrument at SwissFEL 37 (proposal #20181741). To follow the time-dependent light–induced dynamics, an optical pump, X-ray probe scheme was used.…”

Mix-and-extrude: high-viscosity sample injection towards time-resolved protein crystallography

“…From previous studies, it is known that flow velocities as low as v = 0.3 mm s À1 are sufficient for stable viscous sample extrusion while maintaining a pulse displacement of ca 30 mm on the sample and, as a result, effectively avoiding exposure of the same crystal with multiple X-ray pulses (Vakili et al, 2022). Moreover, sample delivery to X-rays that arrive at higher pulse repetition rates, as seen at the FELs SACLA (60 Hz), PAL-XFEL (60 Hz), SwissFEL (100 Hz) and LCLS (120 Hz), can also be accommodated (Shimazu et al, 2019;Lee et al, 2020;Milne et al, 2017;Wells et al, 2022). However, for !100 Hz operation, a sample width reduction from 75 to 50 mm is highly recommended.…”