Elastic Properties of the Pyrite‐Type FeOOH‐AlOOH System From First‐Principles Calculations
Elastic Properties of the Pyrite‐Type FeOOH‐AlOOH System From First‐Principles Calculations
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根据第一原理计算黄铁矿型 FeOOH-AlOOH 体系的弹性性质
DOI：
10.1029/2021gc009703
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Tsuchiya, Jun
中科院分区：
文献类型：
--
作者：
Thompson, Elizabeth C.;Campbell, Andrew J.;Tsuchiya, Jun
黄铁矿型（FeS 2结构）FeO 2 H的稳定性，结构和弹性性质使用基于密度泛函理论的计算与内部一致的库仑自相互作用项（Ueff）确定。将黄铁矿型FeO 2 H的性质与黄铁矿型AlO 2 H的性质进行比较，黄铁矿型AlO 2 H可能在高温下形成固溶体，以及两个端元的各自低压CaCl 2型多晶型物：α-FeOOH和δ-AlOOH。由于这些端元的CaCl 2-型→黄铁矿-型结构转变压力的显著差异，（Al，Fe）O2 H固溶体多晶型物的稳定性预计将在下地幔压力下由成分驱动。由于（Al，Fe）OOH的地球物理性质具有结构依赖性，因此关于黄铁矿型FeO 2 H对地震观测特征的贡献的解释必须考虑到这种广泛的相位环的重要性。考虑到这一点，富铁黄铁矿型（Al，Fe）OOH可能与Al主导的CaCl 2型δ-（Al，Fe）OOH在地球深部共存。此外，黄铁矿型（Al0.5- 0.6，Fe0.4 -0.5）O2 H可以再现地球最低地幔中地震观测到的超低速带的压缩和剪切速度特征，而Al为主但含Fe的CaCl 2型δ-（Al，Fe）OOH可能有助于形成大的低剪切速度区。
The stability, structure, and elastic properties of pyrite‐type (FeS2structured) FeO2H were determined using density functional theory‐based computations with an internally consistent Coulombic self‐interaction term (Ueff). The properties of pyrite‐type FeO2H are compared to that of pyrite‐type AlO2H, with which it likely forms a solid solution at high temperature, as well as the respective lower pressure CaCl2‐type polymorphs of both endmembers:ϵ‐FeOOH andδ‐AlOOH. Due to substantial differences in the CaCl2‐type → pyrite‐type structural transition pressures of these endmembers, the stabilities of the (Al,Fe)O2H solid solution polymorphs are anticipated to be compositionally driven at lower mantle pressures. As the geophysical properties of (Al,Fe)OOH are structurally dependant, interpretations regarding the contribution of pyrite‐type FeO2H to seismically observed features must take into account the importance of this broad phase loop. With this in mind, Fe‐rich pyrite‐type (Al,Fe)OOH may coexist with Al‐dominant CaCl2‐typeδ‐(Al,Fe)OOH in the deep Earth. Furthermore, pyrite‐type (Al0.5–0.6,Fe0.4–0.5)O2H can reproduce the reduced compressional and shear velocities characteristic of seismically observed ultra low velocity zones in the Earth's lowermost mantle while Al‐dominant but Fe‐bearing CaCl2‐typeδ‐(Al,Fe)OOH may contribute to large low shear velocity provinces.
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影响因子：
5.2
作者：
Liang Yuan;E. Ohtani;D. Ikuta;S. Kamada;J. Tsuchiya;Hirao Naohisa;Y. Ohishi;A. Suzuki
通讯作者：
Liang Yuan;E. Ohtani;D. Ikuta;S. Kamada;J. Tsuchiya;Hirao Naohisa;Y. Ohishi;A. Suzuki
影响因子：
3.7
作者：
J. Tsuchiya;T. Tsuchiya
通讯作者：
J. Tsuchiya;T. Tsuchiya
DOI：
10.1093/oso/9780199602025.003.0006
发表时间：
2021-06
期刊：
Physics of Spin-Orbit-Coupled Oxides
影响因子：
--
作者：
G. Cao;L. DeLong
通讯作者：
G. Cao;L. DeLong
影响因子：
5.3
作者：
Panero, Wendy R.;Caracas, Razvan
通讯作者：
Caracas, Razvan
影响因子：
18.3
作者：
Pamato, Martha G.;Myhill, Robert;Miyajima, Nobuyoshi
通讯作者：
Miyajima, Nobuyoshi