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Related papers: Thermoelasticity of Fe2+-bearing bridgmanite

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We report \textit{ab initio} (LDA + U$_{sc}$) calculations of thermoelastic properties of ferric iron (Fe$^{3+}$)- and aluminum (Al)-bearing bridgmanite (MgSiO$_3$ perovskite), the main Earth forming phase, at relevant pressure and…

Materials Science · Physics 2016-03-30 Gaurav Shukla , Matteo Cococcioni , Renata M. Wentzcovitch

Fe and Al are two of the most important rock-forming elements other than Mg, Si, and O. Their presence in the lower mantle's most abundant minerals, MgSiO_3 bridgmanite, MgSiO_3 post-perovskite and MgO periclase, alters their elastic…

Geophysics · Physics 2015-12-22 Shuai Zhang , Sanne Cottaar , Tao Liu , Stephen Stackhouse , Burkhard Militzer

The spin crossover of iron in Fe$^{3+}$-bearing bridgmanite, the most abundant mineral of the Earth's lower mantle, is by now a well-established phenomenon, though several aspects of this crossover remain unclear. Here we investigate…

Materials Science · Physics 2016-10-12 Gaurav Shukla , Renata M. Wentzcovitch

Iron partitioning among the main lower mantle phases, bridgmanite (Bm) and ferropericlase (Fp), has non-monotonic behavior owing to the high-spin to low-spin crossover in ferrous iron (Fe2+) in Fp. Results of previous studies of the iron…

Materials Science · Physics 2024-05-21 Jingyi Zhuang , Renata Wentzcovitch

MgSiO_3-perovskite (MgPv) plays a crucial role in the Earth's lower mantle. This study combines deep-learning potential (DP) with density functional theory (DFT) to investigate the structural and elastic properties of MgPv under lower…

Geophysics · Physics 2023-08-21 Tianqi Wan , Chenxing Luo , Yang Sun , Renata M. Wentzcovitch

The iron spin crossover in ferropericlase introduces anomalies in its thermodynamics and thermoelastic properties. Here we investigate how these anomalies can affect the lower mantle geotherm. The effect is examined in mantle aggregates…

We present LDA+$U_{sc}$ calculations of high-spin (HS) and low-spin (LS) states in ferropericlase (fp) with an iron concentration of 18.75$\%$. The Hubbard parameter $U$ is determined self-consistently with structures optimized at arbitrary…

Geophysics · Physics 2022-04-12 Yang Sun , Jingyi Zhuang , Renata M. Wentzcovitch

Davemaoite (Dm), the cubic phase of CaSiO3-perovskite (CaPv), is a major component of the Earth's lower mantle. Understanding its elastic behavior, including its dissolution in bridgmanite (MgSiO3-perovskite), is crucial for interpreting…

Materials Science · Physics 2025-05-06 Tianqi Wan , Chenxing Luo , Zhen Zhang , Yang Sun , Renata M. Wentzcovitch

Earth's lower mantle is generally believed to be seismically and chemically homogeneous because most of the key seismic parameters can be explained using a simplified mineralogical model at expected press-temperature conditions. However,…

Materials Science · Physics 2017-04-06 Shenzhen Xu , Jung-Fu Lin , Dane Morgan

We have studied the ferrous (Fe2+) and ferric (Fe3+) iron concentrations in Al-free Fe containing Mg-silicate perovskite (Mg-Pv) at pressure (P), temperature (T), and oxygen fugacity (fO2) conditions related to the lower mantle using a…

Earth and Planetary Astrophysics · Physics 2016-07-12 Shenzhen Xu , Sang-Heon Shim , Dane Morgan

We combine density functional theory (DFT) within the local density approximation (LDA), the quasiharmonic approximation (QHA), and a model vibrational density of states (VDoS) to calculate elastic moduli and sound velocities of…

Materials Science · Physics 2015-06-05 M. Núñez Valdez , Z. Wu , Y. G. Yu , J. Revenaugh , R. M. Wentzcovitch

Ferroelasticity describes a phenomenon in which a material exhibits two or more equally stable orientation variants and can be switched from one form to another under an applied stress. Recent works have demonstrated that two-dimensional…

Materials Science · Physics 2024-09-11 Devesh R. Kripalani , Qiye Guan , Hejin Yan , Yongqing Cai , Kun Zhou

The thermoelastic properties of ferropericlase Mg1-xFexO (x = 0.1875) throughout the iron high-to-low spin crossover have been investigated by first principles at Earth's lower mantle conditions. This crossover has important consequences…

Materials Science · Physics 2013-07-15 R. M. Wentzcovitch , J. F. Justo , Z. Wu , C. R. S. da Silva , D. A. Yuen , D. Kohlstedt

Iron spin transition directly affects properties of lower mantle minerals and can thus alter geophysical and geochemical characteristics of the deep Earth. While the spin transition in ferropericlase has been vigorously established at P ~…

The elastic, thermodynamic, and electronic properties of fluorite RuO_2 under high pressure are investigated by plane-wave pseudopotential density functional theory. The optimized lattice parameters, elastic constants, bulk modulus, and…

Materials Science · Physics 2017-08-23 Z. J. Yang , A. M. Guo , Y. D. Guo , J. Li , Z. Wang , Q. Liu , R. F. Linghu , X. D. Yang

BaFe$_2$S$_3$ is a quasi-one-dimensional antiferromagnetic insulator that becomes superconducting under hydrostatic pressure. The magnetic ordering temperature, $T_N$, as well as the presence of superconductivity have been found to be…

Superconductivity · Physics 2021-09-15 M. L. Amigó , Q. Stahl , A. Maljuk , A. U. B. Wolter , C. Hess , J. Geck , S. Wurmehl , S. Seiro , B. Büchner

Here, we study the electrical transport and specific heat in 4$d$ based ferromagnetic material SrRuO$_3$ and its Ti substituted SrRu$_{1-x}$Ti$_x$O$_3$ series ($x$ $\le$ 0.7). The SrRuO$_3$ is a metal and shows itinerant ferromagnetism with…

Strongly Correlated Electrons · Physics 2020-09-02 Renu Gupta , R. Rawat , A. K. Pramanik

We present a detailed theoretical study of the electronic, magnetic, and structural properties of magnesiow\"ustite Fe$_{1-x}$Mg$_x$O with $x$ in the range between 0$-$0.875 using a fully charge self-consistent implementation of the density…

Strongly Correlated Electrons · Physics 2017-08-24 I. Leonov , A. Ponomareva , R. Nazarov , I. A. Abrikosov

Spin crossover of iron is of central importance in solid Earth geophysics. It impacts all physical properties of minerals that altogether constitute $\sim 95$ vol\% of the Earth's lower mantle: ferropericlase [(Mg,Fe)O] and Fe-bearing…

Strongly Correlated Electrons · Physics 2015-06-23 Han Hsu , Renata M. Wentzcovitch

The primary phase of the Earth's lower mantle, (Al, Fe)-bearing bridgmanite, transitions to the postperovskite (PPv) phase at Earth's deep mantle conditions. Despite extensive experimental and ab initio investigations, there are still…

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