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arXiv · 2105.05562

Procedure for 3D atomic resolution reconstructions using atom-counting and a Bayesian genetic algorithm

Annick De Backer·Sandra Van Aert·Peter D. Nellist·Lewys Jones
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Abstract

We introduce a Bayesian genetic algorithm for reconstructing atomic models of nanoparticles from a single projection using Z-contrast imaging. The number of atoms in a projected atomic column obtained from annular dark field scanning transmission electron microscopy (ADF STEM) images serves as an input for the initial three-dimensional (3D) model. The novel algorithm minimizes the energy of the structure while utilizing a priori information about the finite precision of the atom-counting results and neighbor-mass relations. The results show excellent prospects for obtaining reliable reconstructions of beam-sensitive nanoparticles during dynamical processes from images acquired with sufficiently low incident electron doses.

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Annick De Backer, Sandra Van Aert, Peter D. Nellist, Lewys Jones. 2021-05-12. Procedure for 3D atomic resolution reconstructions using atom-counting and a Bayesian genetic algorithm. https://arxiv.org/abs/2105.05562

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