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相关论文: Shock Response and Phase Transitions of MgO at Pla…

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Earth and Moon are shown here to be composed of oxygen isotope reservoirs that are indistinguishable, with a difference in {\Delta}"17O of -1 +/- 5ppm (2se). Based on these data and our new planet formation simulations that include a…

地球与行星天体物理 · 物理学 2016-03-16 Edward D. Young , Issaku E. Kohl , Paul H. Warren , David C. Rubie , Seth A. Jacobson , Alessandro Morbidelli

Realistic oxide materials are often semiconductors, in particular at elevated temperatures, and their surfaces contain undercoordiated atoms at structural defects such as steps and corners. Using hybrid density-functional theory and ab…

Fe-bearing MgO [(Mg$_{1-x}$Fe$_x$)O] is considered a major constituent of terrestrial exoplanets. Crystallizing in the B1 structure in the Earth's lower mantle, (Mg$_{1-x}$Fe$_x$)O undergoes a high-spin ($S=2$) to low-spin ($S=0$)…

材料科学 · 物理学 2022-05-20 Han Hsu , Koichiro Umemoto

The stability of MgH$_2$ has been studied up to 20~GPa using density-functional total-energy calculations. At ambient pressure $\alpha$-MgH${_2}$ takes a TiO$_2$-rutile-type structure. $\alpha$-MgH$_2$ is predicted to transform into…

材料科学 · 物理学 2009-11-07 P. Vajeeston , P. Ravindran , A. Kjekshus , H. Fjellvåg

Carbon dioxide is one of the major contributors to the radiative forcing, increasing both the temperature and the humidity of Earth's atmosphere. If the stellar irradiance increases and water becomes abundant in the stratosphere of an…

地球与行星天体物理 · 物理学 2019-01-11 Illeana Gomez-Leal , Lisa Kaltenegger , Valerio Lucarini , Frank Lunkeit

Terrestrial exoplanets are of great interest for being simultaneously similar to and different from Earth. Their compositions are likely comparable to those of solar-terrestrial objects, but their internal pressures and temperatures can…

We report ab initio calculations of the melting curve and Hugoniot of molybdenum for the pressure range 0-400 GPa, using density functional theory (DFT) in the projector augmented wave (PAW) implementation. We use the ``reference…

材料科学 · 物理学 2009-11-13 C. Cazorla , M. J. Gillan , S. Taioli , D. Alfè

The melting curve for MgO was obtained using molecular dynamics and a non-empirical, many-body potential. We also studied premelting effects by computing the dynamical structure factor in the crystal on approach to melting. The melting…

mtrl-th · 物理学 2008-02-03 R. E. Cohen , J. S. Weitz

Using two first-principles computer simulation techniques, path integral Monte-Carlo and density functional theory molecular dynamics, we derive the equation of state of magnesium in the regime of warm dense matter, with densities ranging…

材料科学 · 物理学 2020-08-20 Felipe González-Cataldo , François Soubiran , Burkhard Militzer

Fe, Mg, and O are among the most abundant elements in terrestrial planets. While the behavior of the Fe-O, Mg-O, and Fe-Mg binary systems under pressure have been investigated, there are still very few studies of the Fe-Mg-O ternary system…

Pressure is a key parameter in the physics and chemistry of planet formation and evolution. Previous studies have erroneously assumed that internal pressures monotonically increase with the mass of a body. Using smoothed particle…

地球与行星天体物理 · 物理学 2020-06-04 Simon J. Lock , Sarah T. Stewart

Mn3TeO6 (MTO) has been experimentally found to adopt a P21/n structure under high pressure, which exhibits a significantly smaller band gap compared to the atmospheric R-3 phase. In this study, we systematically investigate the magnetism,…

材料科学 · 物理学 2024-07-23 Xiao-Long Pan , Hao Wang , Lei Liu , Xiang-Rong Chen , Hua Y. Geng

A mixture of Mg and MgO has been subjected to a shock-wave pressure of 170 kbar. The ac susceptibility measurements of the product has revealed a metastable superconductivity with Tc=30 K, characterized by glassy dynamics of the shielding…

In order to provide a comprehensive theoretical description of MgSiO$_3$ at extreme conditions, we combine results from path integral Monte Carlo (PIMC) and density functional molecular dynamics simulations (DFT-MD) and generate a…

The Mg-Si-O system is the major Earth and rocky planet-forming system. Here, through quantum variable-composition evolutionary structure explorations, we have discovered several unexpected stable binary and ternary compounds in the Mg-Si-O…

地球物理 · 物理学 2015-10-13 Haiyang Niu , Artem R. Oganov , Xing-Qiu Chen , Dianzhong Li

Similarities in the non-mass dependent isotopic composition of refractory elements with the bulk silicate Earth suggest that both the Earth and the Moon formed from the same material reservoir. On the other hand, the Moon's volatile…

地球与行星天体物理 · 物理学 2024-12-03 Gustavo Madeira , Leandro Esteves , Sebastien Charnoz , Elena Lega , Frederic Moynier

The magma ocean (MO) is a crucial stage in the build-up of terrestrial planets. Its solidification and the accompanying outgassing of volatiles set the conditions for important processes occurring later or even simultaneously, such as…

地球与行星天体物理 · 物理学 2019-04-11 Athanasia Nikolaou , Nisha Katyal , Nicola Tosi , Mareike Godolt , John Lee Grenfell , Heike Rauer

According to the standard giant impact hypothesis, the Moon formed from a partially vaporized disk generated by a collision between the proto Earth and a Mars sized impactor. The initial structure of the disk significantly affects the Moon…

地球与行星天体物理 · 物理学 2014-01-15 Miki Nakajima , David J. Stevenson

There has been a major controversy over the past seven years about the high-pressure melting curves of transition metals. Static compression (diamond-anvil cell: DAC) experiments up to the Mbar region give very low melting slopes dT_m/dP,…

材料科学 · 物理学 2009-11-13 C. Cazorla , D. Alfè , M. J. Gillan

Mg2GeO4 is an analogue for the ultra-high pressure behavior of Mg2SiO4, so we have investigated magnesium germanate to 275 GPa and over 2000 K using a laser-heated diamond anvil cell combined with in situ synchrotron X-ray diffraction and…