X-ray imaging with grating interferometry has previously been regarded as a technique providing information only in direct space. It delivers absorption, phase, and dark-field contrast, which can be viewed as parameters of the underlying but unresolved scattering distribution. Here, we present a method that provides the ultrasmall-angle x-ray scattering distribution and, thus, allows simultaneous access to direct and reciprocal space information.

Colloidal superlattices are fascinating materials made of ordered nanocrystals, yet they are rarely called “atomically precise”. That is unsurprising, given how challenging it is to quantify the degree of structural order in these materials. However, once that order crosses a certain threshold, the constructive interference of X-rays diffracted by the nanocrystals dominates the diffraction pattern, offering a wealth of structural information. By treating nanocrystals as scattering sources forming a self-probing interferometer, we developed a multilayer diffraction method that enabled the accurate determination of the nanocrystal size, interparticle spacing, and their fluctuations for samples of self-assembled CsPbBr3 and PbS nanomaterials. The multilayer diffraction method requires only a laboratory-grade diffractometer and an open-source fitting algorithm for data analysis. The average nanocrystal displacement of 0.33 to 1.43 Å in the studied superlattices provides a figure of merit for their structural perfection and approaches the atomic displacement parameters found in traditional crystals.

Colloidal superlattices are fascinating materials made of ordered nanocrystals, yet they are rarely called “atomically precise.” That is unsurprising, given how challenging it is to quantify the degree of structural order in these materials. However, once that order crosses a certain threshold, constructive interference of X-rays diffracted by the nanocrystals dominates the diffraction pattern, offering a wealth of structural information. By treating nanocrystals as scattering sources forming a self-probing interferometer, we developed a multilayer diffraction method that enabled the accurate determination of nanocrystal size, interparticle spacing, and their fluctuations for samples of self-assembled CsPbBr₃ and PbS nanomaterials. The average nanocrystal displacement of 0.32-1.4 Å in the studied superlattices provides a figure of merit for their structural perfection and approaches the atomic displacement parameters found in traditional crystals. The method requires a laboratory-grade diffractometer and an open-source fitting algorithm for data analysis, providing a competitive alternative to resource-intensive synchrotron experiments.

SUNBIM (supramolecular and submolecular nano-and biomaterials X-ray imaging) is a suite of integrated programs which, through a user-friendly graphical user interface, are optimized to perform the following: (i) q-scale calibration and two-dimensional ! one-dimensional folding on small-and wide-angle X-ray scattering (SAXS/WAXS) and grazing-incidence SAXS/ WAXS (GISAXS/GIWAXS) data, also including possible eccentricity corrections for WAXS/GIWAXS data; (ii) background evaluation and subtraction, denoising, and deconvolution of the primary beam angular divergence on SAXS/GISAXS profiles; (iii) indexing of two-dimensional GISAXS frames and extraction of one-dimensional GISAXS profiles along specific cuts; (iv) scanning microscopy in absorption and SAXS contrast. The latter includes collection of transmission and SAXS data, respectively, in a mesh across a mm 2 area, organization of the as-collected data into a single composite image of transmission values or two-dimensional SAXS frames, analysis of the composed data to derive the absorption map and/or the spatial distribution, and orientation of nanoscale structures over the scanned area.