Advanced electron crystallography through model-based imaging

The increasing need for precise determination of the atomic arrangement of non-periodic structures in materials design and the control of nanostructures explains the growing interest in quantitative transmission electron microscopy. The aim is to extract precise and accurate numbers for unknown stru...

Full description

Saved in:
Bibliographic Details
Published in:IUCrJ 2016-01, Vol.3 (Pt 1), p.71-83
Main Authors: Van Aert, Sandra, De Backer, Annick, Martinez, Gerardo T, den Dekker, Arnold J, Van Dyck, Dirk, Bals, Sara, Van Tendeloo, Gustaaf
Format: Article
Language:English
Subjects:
Atomic force microscopy
Atomic properties
Atomic structure
Crystallography
Electron microscopy
experimental design
Image transmission
Mathematical models
Methods
Nanostructure
Parameters
quantitative analysis
Readers
statistical parameter estimation
structure refinement
transmission electron microscopy
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The increasing need for precise determination of the atomic arrangement of non-periodic structures in materials design and the control of nanostructures explains the growing interest in quantitative transmission electron microscopy. The aim is to extract precise and accurate numbers for unknown structure parameters including atomic positions, chemical concentrations and atomic numbers. For this purpose, statistical parameter estimation theory has been shown to provide reliable results. In this theory, observations are considered purely as data planes, from which structure parameters have to be determined using a parametric model describing the images. As such, the positions of atom columns can be measured with a precision of the order of a few picometres, even though the resolution of the electron microscope is still one or two orders of magnitude larger. Moreover, small differences in average atomic number, which cannot be distinguished visually, can be quantified using high-angle annular dark-field scanning transmission electron microscopy images. In addition, this theory allows one to measure compositional changes at interfaces, to count atoms with single-atom sensitivity, and to reconstruct atomic structures in three dimensions. This feature article brings the reader up to date, summarizing the underlying theory and highlighting some of the recent applications of quantitative model-based transmisson electron microscopy.
ISSN:2052-2525
2052-2525
DOI:10.1107/S2052252515019727