Insights into the structural complexity and local disorder of crystalline AsTe3 from semi-automated first-principles modelling
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Summary
This summary is machine-generated.We developed a computational workflow to solve the crystal structure of AsTe3, revealing defects crucial for its thermoelectric properties. This aids in understanding and optimizing advanced thermoelectric materials.
Area Of Science
- Materials Science
- Computational Materials Science
- Solid State Chemistry
Background
- Crystalline AsTe3 exhibits promising thermoelectric properties, but its structure remains unsolved.
- Understanding the atomic structure is key to optimizing thermoelectric performance.
Purpose Of The Study
- To elucidate the complex crystal structure of AsTe3 using atomic-scale modeling.
- To investigate the role of As/Te disorder and defects in the material's structure and properties.
Main Methods
- A semi-automated workflow combining combinatorial structure generation, density functional theory (DFT) calculations, and multi-criterion evaluation.
- Utilizing experimental data from X-ray total scattering and diffraction as a basis for structural templates.
Main Results
- Identified high-quality structural models featuring intergrowth domains ( < 1 nm) composed of elemental Te (Te_el) and alpha-As2Te3.
- Observed that defects, arising from varying domain thicknesses and arrangements, are intrinsic to crystalline AsTe3.
- Electronic bandgap predictions align well with experimental values, and defects may enhance electronic conductivity.
Conclusions
- The study reveals the intricate defect structure of crystalline AsTe3, crucial for its thermoelectric behavior.
- The developed computational workflow provides a robust method for investigating complex material structures.
- Insights into structural defects offer pathways for designing improved thermoelectric materials.
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