2004年
Phase transition in MgSiO3 perovskite in the earth's lower mantle
Earth and Planetary Science Letters
- ,
- ,
- ,
- 巻
- 224
- 号
- 3-4
- 開始ページ
- 241
- 終了ページ
- 248
- 記述言語
- 英語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1016/j.epsl.2004.05.017
A new polymorph of MgSiO3 more stable than the Pbnm -perovskite phase has been identified by first-principles computations. It has the CaIrO3 structure with Cmcm symmetry and consists of SiO3 layers intercalated by eightfold-coordinated Mg ions. High-temperature calculations within the quasiharmonic approximation give a volume change of ∼1.5% and a Clapeyron slope of ∼7.5±0.3 MPa/K at ∼2750 K and ∼125 GPa. These pressure-temperature (P-T) conditions are close to those in which a phase transition in MgSiO3-perovskite has been observed by in situ angle dispersive X-ray diffraction measurements. This transition appears to be associated with the D″ discontinuity. © 2004 Elsevier B.V. All rights reserved.
- リンク情報
- ID情報
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- DOI : 10.1016/j.epsl.2004.05.017
- ISSN : 0012-821X
- ORCIDのPut Code : 49519612
- SCOPUS ID : 3342887951