Kinematic HAADF-STEM image simulation of small nanoparticles.

The high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) has been widely used in nanoparticle characterization due to its relatively straightforward interpretability, although multislice simulation is often required in order to take into account the strong dynamical screening effect if quantitative structure information is needed. The multislice simulation is very time-consuming, which can be a hurdle in cases when one has to deal with a large set of images. In this paper, we introduce a simple computer program, based on kinematic-scattering method, which allows users to simulate HAADF-STEM images of small nanoparticles, in 'real time' on a standard desktop computer. By comparing with the sophisticated multislice simulation, we demonstrate that such an approach is adequate for nanoparticles of ∼3 nm in diameter (assuming an approximately spherical shape), particularly away from strict zone axis conditions. As an application, we show that the efficient kinematic simulation allows quick identification of orientation of nanoparticles.