Abstract
The tetragonal to orthorhombic ferroelastic phase transition between rutile- and CaCl2-type SiO2 at high pressures is studied using first-principles calculations and the Landau free-energy expansion. The phase transition is systematically investigated in terms of characteristic phonon modes with B1g and Ag symmetries, shear moduli, transverse-acoustic mode, rotation angle of the SiO6 octahedra, spontaneous symmetry-breaking and volume strains, and enthalpy. The results show that these physical behaviors at the transition are well described using the Landau free-energy expansion parametrized by the first-principles calculations.
Keywords
Tetragonal crystal systemPhase transitionCondensed matter physicsMaterials scienceEnergy (signal processing)Orthorhombic crystal systemRutileOctahedronPhononType (biology)PhysicsThermodynamicsPhase (matter)CrystallographyCrystal structureDiffractionQuantum mechanicsChemistry
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Publication Info
- Year
- 2008
- Type
- article
- Volume
- 78
- Issue
- 13
- Citations
- 5250
- Access
- Closed
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Atsushi Togo,
Fumiyasu Oba,
Isao Tanaka
(2008).
First-principles calculations of the ferroelastic transition between rutile-type and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mtext>CaCl</mml:mtext></mml:mrow><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>-type<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mtext>SiO</mml:mtext></mml:mrow><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>at high pressures.
Physical Review B
, 78
(13)
.
https://doi.org/10.1103/physrevb.78.134106
Identifiers
- DOI
- 10.1103/physrevb.78.134106