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Structure and stability of alpha- and beta-Ti2Se. Electron diffraction versus density-functional theory calculations
Karsten Albe1, Thomas E Weirich
1Technische Universität Darmstadt, Institut für Materialwissenschaft, Petersenstrasse 23, Germany. albe@tu-darmstadt.de
Acta Crystallographica. Section A, Foundations of Crystallography
|December 24, 2002
Summary
Researchers validated titanium selenide (Ti(2)Se) crystal structures using advanced computational methods. Total energy calculations confirmed experimental findings and predicted a new high-pressure phase for beta-Ti(2)Se.
Area of Science:
- Materials Science
- Solid-State Physics
- Crystallography
Background:
- Nanosize crystallites of titanium selenide (Ti(2)Se) exhibit alpha and beta structural modifications.
- Electron diffraction analysis has characterized these structures.
Purpose of the Study:
- To validate experimental findings for Ti(2)Se structures using theoretical calculations.
- To investigate the stability and properties of alpha- and beta-Ti(2)Se.
- To assess the utility of electron diffraction for solving unknown crystal structures.
Main Methods:
- Total energy calculations.
- Non-local density-functional theory (DFT).
- Equation of state analysis.
Main Results:
- Calculated structural parameters for both alpha- and beta-Ti(2)Se show excellent agreement with experimental electron microscopy data.
- Beta-Ti(2)Se is theoretically predicted to be a high-pressure phase.
- Electron diffraction data can accurately solve and refine unknown crystal structures.
Conclusions:
- Theoretical calculations confirm the experimental characterization of Ti(2)Se structures.
- Electron diffraction is a powerful technique for structural determination of novel materials.
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