About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
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Characterization of Minerals, Metals and Materials
|
Presentation Title |
Composition Determination of Atomic Columns in Misfit-layered Cobalt Oxide by Bloch-wave-based HAADF-STEM Image Simulation |
Author(s) |
Takao Morimura, Tomoya Hiwatashi, Shin-ichiro Kondo |
On-Site Speaker (Planned) |
Takao Morimura |
Abstract Scope |
In a Bloch-wave-based STEM image simulation, a framework for calculating the cross section for any incoherent scattering process was formulated by Allen et al. They simulated the HAADF, BSE, EELS and EDX STEM images from the inelastic scattering coefficients. The present authors extended Allens' approach to a layer-by-layer representation for application to inhomogeneous samples. Calculations for a multi-layer Si samples were performed by multiplying Allens’ scattering matrices. In the present work, our approach was applied to misfit-layered cobalt oxide Ca-Co-O, which is high performance thermoelectric material and possesses extremely complicated crystal structure. The relationship between the occupancies of doped Sr in Ca atomic columns and the HAADF-STEM image intensities were calculated by the layer-by-layer Bloch wave approach at the various experimental conditions. The Sr occupancies were determined and the accuracies were discussed. |
Proceedings Inclusion? |
Planned: |