Three-dimensional femtosecond snapshots of isolated faceted nanostructures

Abstract

The structure and dynamics of isolated nanosamples in free flight can be directly visualized via single-shot coherent diffractive imaging using the intense and short pulses of x-ray free-electron lasers. Wide-angle scattering images encode three-dimensional (3D) morphological information of the samples, but its retrieval remains a challenge. Up to now, effective 3D morphology reconstructions from single shots were only achieved via fitting with highly constrained models, requiring a priori knowledge about possible geometries. Here, we present a much more generic imaging approach. Relying on a model that allows for any sample morphology described by a convex polyhedron, we reconstruct wide-angle diffraction patterns from individual silver nanoparticles. In addition to known structural motives with high symmetries, we retrieve imperfect shapes and agglomerates that were not previously accessible. Our results open unexplored routes toward true 3D structure determination of single nanoparticles and, ultimately, 3D movies of ultrafast nanoscale dynamics.

Autonomous x-ray scattering

“…The data analysis step can also be automated in a variety of ways. The analysis pipeline can leverage existing analysis methods and software [51,62], or use a ML method optimized for the particular kind of x-ray data: scattering [63][64][65][66][67][68][69][70][71][72], diffraction [73][74][75][76][77][78][79] and crystallography [80,81], reflectivity [82][83][84], imaging [85][86][87][88][89][90][91], spectroscopy [92][93][94], photon correlation spectroscopy [95,96], or XFEL pulsed experiments [10,97,98] and single-particle diffraction [73,[99][100][101]. In all cases, analysis code must be wrapped in a workflow manager that can automatically trigger the analysis pipeline as soon as new data is collected.…”