Techniques for quantitative HREM analysis of structure and displacements at interfacial steps, facets and facet junctions

Conference · Tue Dec 31 04:00:00 EST 1996

OSTI ID:468753

Dahmen, U ^[1]; Michel, D; Hyetch, M ^[2]; Paciornik, S ^[3]

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1. Lawrence Berkeley National Lab., CA (United States)
2. CECM-CNRS, Vitry sur Seine (France)
3. DCMM, PUC-Rio (Brazil)

Quantitative High Resolution Electron Microscopy (QHREM) has made considerable recent advances in the analysis of localized atomic structure, especially in flat, periodic interfaces. This is largely due to the increased speed and sophistication of computer algorithms that compare experimental and simulated images, and to strategies for refining this comparison. However, defects such as dislocations, disclinations or steps often lead to elastic distortion fields in the experimental image that are not included in the simulations of an idealized interface. We describe quantitative techniques to measure atomic structure and displacement fields in these two different regimes, and to refine the structure of the core when defects lead to deviations from ideal periodic conditions. For the regime of the localized structure, we have introduced a template matching technique which measures the precise location and similarity of structural units characteristic for an interface structure. In the regime of longer-range displacement fields, the moire technique and the closely related geometrical phase technique have been shown to be useful quantitative tools.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 468753
• Report Number(s): CONF-960877--
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTAL DEFECTS
ELECTRON MICROSCOPY
GRAIN BOUNDARIES
IMAGES
RUTILE
TITANIUM OXIDES