Making sense of nanocrystal lattice fringes

TL;DR

This paper introduces fringe-visibility maps as a powerful tool for analyzing nanocrystal lattice fringes, enabling 3D crystallographic insights and thickness measurements from lattice images with modest tilts.

Contribution

It presents fringe-visibility maps as a novel method to quantify lattice fringes and extract 3D crystallographic information from nanocrystal images.

Findings

Fringe-visibility maps help determine 3D lattice parameters.

They enable 'fringe fingerprinting' of randomly-oriented particles.

The method improves with higher resolution imaging and precise tilting.

Abstract

The orientation-dependence of thin-crystal lattice fringes can be gracefully quantified using fringe-visibility maps, a direct-space analog of Kikuchi maps. As in navigation of reciprocal space with the aid of Kikuchi lines, fringe-visibility maps facilitate acquisition of 3D crystallographic information in lattice images. In particular, these maps can help researchers to determine the 3D lattice parameters of individual nano-crystals, to ``fringe fingerprint'' collections of randomly-oriented particles, and to measure local specimen-thickness with only modest tilt. Since the number of fringes in an image increases with maximum spatial-frequency squared, these strategies (with help from more precise goniometers) will be more useful as aberration-correction moves resolutions into the subangstrom range.