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Recovery of undamaged electron-density maps in the presence of damage-induced partial coherence in single-particle imaging

Resolving the electronic structure of single biological molecules in their native state was among the primary motivations behind X-ray free-electron lasers. The ultra-short pulses they produce can outrun the atomic motion induced by radiation damage, …

Fluctuation X-ray diffraction reveals three-dimensional nanostructure and disorder in self-assembled lipidphases

Emergent nanoscale order in materials such as self-assembled lipid phases, colloidal materials and metal-organic frameworks is often characterized by small-angle X-ray scattering (SAXS). Frequently, residual disorder in these materials prevents …

Hybrid Plasma/Molecular-Dynamics Approach for Efficient XFEL Radiation Damage Simulations

X-ray free-electron laser pulses initiate a complex series of changes to the electronic and nuclear structure of matter on femtosecond timescales. These damage processes include widespread ionization, the formation of a quasi-plasma state and the …

Spatial resolution and signal-to-noise ratio in x-ray imaging

X-ray free-electron lasers (XFELs) enable crystallographic structure determination beyond the limitations imposed upon synchrotron measurements by radiation damage. The need for very short XFEL pulses is relieved through gating of Bragg diffraction …

Noise-resolution uncertainty principle in classical and quantum systems

We show that the width of an arbitrary function and the width of the distribution of its values cannot be made arbitrarily small simultaneously. In the case of ergodic stochastic processes, an ensuing uncertainty relationship is then demonstrated for …

Relative roles of multiple scattering and Fresnel diffraction in the imaging of small molecules using electrons

The relative roles of multiple electron scattering and in-molecule Fresnel diffraction in atomic-resolution transmission electron microscopy of small molecules are discussed. It is argued that, while multiple scattering tends to have only a moderate …

Effect of radiation damage and illumination variability on signal-to-noise ratio in XFEL single-particle imaging

The deterioration of both the signal-to-noise ratio and the spatial resolution in the electron-density distribution reconstructed from diffraction intensities collected at different orientations of a sample is analysed theoretically with respect to …

On electron imaging of small molecules, Part II: tomographic reconstruction from defocus series

A practical method utilising three-dimensional image pattern matching is proposed which, in principle, is capable of unambiguous determination of the types and positions of atoms in small molecules from defocus series collected at only a few …

Spatial resolution, noise and information in the computational-imaging era

Imaging is an important means by which information is gathered regarding the physical world. Spatial resolution and signal-to-noise ratio are underpinning concepts. There is a paucity of rigorous definitions for these quantities, which are general …

Spatial resolution and signal-to-noise ratio in x-ray imaging

The notions of spatial resolution and signal-to-noise are central to most forms of imaging. However, it appears that rigorous definitions of these quantities, which would be general enough to be useful in a broad range of imaging problems, while …