A Database of Convergent Beam Electron Diffraction Patterns for Machine Learning of the Structural Properties of Materials
- Laanait, Nouamane | Oak Ridge National Laboratory
- Borisevich, Albina | Oak Ridge National Laboratory
- Yin, Junqi | Oak Ridge National Laboratory
Overview
Description
State of the art electron microscopes produce focused electron beams with atomic dimensions and allow to capture diffraction patterns arising from the interaction of incident electrons with nanoscale material volumes. Backing out the local atomic structure of said materials requires compute- and time-intensive analyses of these diffraction patterns (known as convergent beam electron diffraction, CBED). Traditional analyses of CBED requires iterative numerical solutions of partial differential equations and comparison with experimental data to refine the starting material configuration. This process is repeated anew for every newly acquired experimental CBED pattern and/or probed material. In this data, we used newly developed multi-GPU and multi-node electron scattering simulation codes on the Summit supercomputer to generate CBED patterns from over 60,000 materials (solid-state materials), representing nearly every known crystal structure. The overarching goals of this data challenge is to: (1) explore the suitability of machine learning algorithms in the advanced analysis of CBED and (2) produce a machine learning algorithm capable of overcoming intrinsic difficulties posed by scientific datasets. The data set is split across multiple HDF5 files and an accompanying Jupyter Notebook provides a detailed description on how to navigate the file structure to access the data samples and the associated materials properties. Briefly, a data sample from this data set is given by a 3-d array formed by stacking 3 CBED patterns simulated from the same material at 3 distinct material projections (i.e. crystallographic orientations). Each CBED pattern is a 2-d array (512x512 pixels) with float 32-bit image intensities. Associated with each data sample in the data set is a host of material attributes or properties which are, in principle, retrievable via analysis of this CBED stack. These consists of the crystal space group the material belongs to, atomic lattice constants and angles, chemical composition, to name but a few. Of note is the crystal space group attributed (or label). All possible spatial arrangements of atoms in any solid (crystal) material obey symmetry conditions described by 230 unique mathematical discrete space groups. Data generation utilized an award of computer time provided by the INCITE program.
Funding resources
DOE contract number
DE-AC05-00OR22725Originating research organization
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)Sponsoring organization
Office of Science (SC), Advanced Scientific Computing Research (ASCR) (SC-21)Details
DOI
10.13139/OLCF/1510313Release date
May 2, 2019Dataset
Dataset type
ND Numeric DataSoftware
HDF5Acknowledgements
Users should acknowledge the OLCF in all publications and presentations that speak to work performed on OLCF resources:
This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC05-00OR22725.
Category
- 36 MATERIALS SCIENCE
Keywords
- Scanning Transmission Electron Microscopy