Intersections of two stacking faults in zincblende GaN
| Autor: | Roman Gröger, Zdeněk Antoš, Petr Vacek |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
geography
geography.geographical_feature_category Materials science General Computer Science Plane (geometry) Stacking General Physics and Astronomy Geometry 02 engineering and technology General Chemistry Fault (geology) Type (model theory) 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Computational Mathematics Intersection Mechanics of Materials General Materials Science 0210 nano-technology Energy (signal processing) Stacking fault Wurtzite crystal structure |
| Zdroj: | Computational Materials Science. 180:109620 |
| ISSN: | 0927-0256 |
| Popis: | The structure and energetics of an isolated { 1 1 1 } stacking fault and the interactions of two non-coplanar { 1 1 1 } stacking faults in zincblende GaN are investigated using an empirical potential of the Tersoff-Brenner type. For a single stacking fault, a metastable configuration is found only when the fault is created on the { 1 1 1 } plane in the glide set, which results in local transformation into a more stable wurtzite structure. This energetically favorable configuration is separated from the unfaulted crystal by a large energy barrier. Interactions between two stacking faults on non-coplanar { 1 1 1 } planes, where one fault corresponds to the metastable configuration created in the glide set and the second fault is created on a different { 1 1 1 } plane, lead to a reduction of the aforementioned energy barrier and an increase of the energy of the second metastable fault. The intersection of the two faults results in a significant reconstruction of atomic positions around the line common to both faults. Apart from the wurtzite stacking, the structure of this intersection shows a partial transformation into the rocksalt structure that is normally stable only at high pressures. The presence of this high-energy rocksalt structure is avoided if the second fault is non-planar. In this case, four different structures of the intersection exist. We demonstrate that one of these structures agrees well with TEM observations. |
| Databáze: | OpenAIRE |
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