### Abstract

The stability of cubic CaSiO_{3} perovskite with respect to octahedral rotations is investigated by ab initio total-energy calculations. The proposed theoretical ground-state crystal structure has the orthorhombic Pbnm symmetry, Pressure gradually reduces the average tilting of the SiO_{6} octahedra relative to the cubic axis, from 7° at zero pressure to 4° at about 150 GPa. The energy difference between the orthorhombic and cubic phases at 0 GPa is 63 meV per f.u. and shows weak pressure dependence. A possible stabilization of the cubic phase at finite temperatures by entropy effects is discussed.

Original language | English |
---|---|

Article number | 193107 |

Pages (from-to) | 1931071-1931074 |

Number of pages | 4 |

Journal | Physical Review B - Condensed Matter and Materials Physics |

Volume | 65 |

Issue number | 19 |

Publication status | Published - May 15 2002 |

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### ASJC Scopus subject areas

- Condensed Matter Physics

### Cite this

_{3}perovskite: An ab initio total energy study.

*Physical Review B - Condensed Matter and Materials Physics*,

*65*(19), 1931071-1931074. [193107].

**Low-temperature crystal structure of CaSiO _{3} perovskite : An ab initio total energy study.** / Magyari-Köpe, B.; Vitos, L.; Grimvall, G.; Johansson, B.; Kollár, J.

Research output: Contribution to journal › Article

_{3}perovskite: An ab initio total energy study',

*Physical Review B - Condensed Matter and Materials Physics*, vol. 65, no. 19, 193107, pp. 1931071-1931074.

_{3}perovskite: An ab initio total energy study. Physical Review B - Condensed Matter and Materials Physics. 2002 May 15;65(19):1931071-1931074. 193107.

}

TY - JOUR

T1 - Low-temperature crystal structure of CaSiO3 perovskite

T2 - An ab initio total energy study

AU - Magyari-Köpe, B.

AU - Vitos, L.

AU - Grimvall, G.

AU - Johansson, B.

AU - Kollár, J.

PY - 2002/5/15

Y1 - 2002/5/15

N2 - The stability of cubic CaSiO3 perovskite with respect to octahedral rotations is investigated by ab initio total-energy calculations. The proposed theoretical ground-state crystal structure has the orthorhombic Pbnm symmetry, Pressure gradually reduces the average tilting of the SiO6 octahedra relative to the cubic axis, from 7° at zero pressure to 4° at about 150 GPa. The energy difference between the orthorhombic and cubic phases at 0 GPa is 63 meV per f.u. and shows weak pressure dependence. A possible stabilization of the cubic phase at finite temperatures by entropy effects is discussed.

AB - The stability of cubic CaSiO3 perovskite with respect to octahedral rotations is investigated by ab initio total-energy calculations. The proposed theoretical ground-state crystal structure has the orthorhombic Pbnm symmetry, Pressure gradually reduces the average tilting of the SiO6 octahedra relative to the cubic axis, from 7° at zero pressure to 4° at about 150 GPa. The energy difference between the orthorhombic and cubic phases at 0 GPa is 63 meV per f.u. and shows weak pressure dependence. A possible stabilization of the cubic phase at finite temperatures by entropy effects is discussed.

UR - http://www.scopus.com/inward/record.url?scp=0037092854&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0037092854&partnerID=8YFLogxK

M3 - Article

VL - 65

SP - 1931071

EP - 1931074

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 0163-1829

IS - 19

M1 - 193107

ER -