The role of transient resonances for ultra-fast imaging of single sucrose nanoclusters

Abstract

Intense x-ray free-electron laser (XFEL) pulses hold great promise for imaging function in nanoscale and biological systems with atomic resolution. So far, however, the spatial resolution obtained from single shot experiments lags averaging static experiments. Here we report on a combined computational and experimental study about ultrafast diffractive imaging of sucrose clusters which are benchmark organic samples. Our theoretical model matches the experimental data from the water window to the keV x-ray regime. The largescale dynamic scattering calculations reveal that transient phenomena driven by non-linear xray interaction are decisive for ultrafast imaging applications. Our study illuminates the complex interplay of the imaging process with the rapidly changing transient electronic structures in XFEL experiments and shows how computational models allow optimization of the parameters for ultrafast imaging experiments.

3D diffractive imaging of nanoparticle ensembles using an x-ray laser

“…3(b), yielding a maximum fluence of around 60 µJ/µm 2 , which leads to a lower bound estimate of around 540 µJ in the focal spot from the measured spot size. The actual fluence was likely higher as the particles were not ideal cubes and the scattering efficiency is reduced at high fluences [31,32]. One can also see that most diffraction patterns were obtained with lower incident fluences, because the particles interacted with the outer regions of the X-ray focus.…”

Photon-In/Photon-Out X-ray Free-Electron Laser Studies of Radiolysis

“…This general approach has allowed EOM-CC-CVS to achieve improved accuracy for single photon transitions [40,81] and expand to two-photon RIXS calculations [82]. Beyond high-level calculations of electronic structure, capturing coreexcited state dynamics poses a further challenge that has been largely pursued with simpler electronic structure methods [72,83,84]. Describing non-local multiple-hole dynamics in complex systems is likely to remain a frontier and foster synergistic research between experiment and theory.…”

Electrospray sample injection for single-particle imaging with X-ray lasers

“…Rubisco particles were sized by fitting the radial diffraction intensities of a sphere model to the radially averaged diffraction intensities of the measurement. To validate our results, we checked that the incident intensity that resulted from the fit fell into the range of intensities expected for the X-ray beam focus 30 . For this calculation we assumed that the particles had the, for proteins characteristic, mass density of 1.35 g/cm 3 Particle sizing by electron microscopy.…”