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The Mg-carbonate-Fe interaction:Implication for the fate of subducted carbonates and formation of diamond in the lower mantle

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Geoscience Frontiers 2019年第4期10卷 1449-1458页

作者： Naira S.Martirosyan Konstantin D. Litasov Sergey S. Lobanov Alexander F. Goncharov Anton Shatskiy Hiroaki Ohfuji vitali prakapenka Sobolev Institute of Geology and Mineralogy Russian Academy of ScienceKoptyuga ave.3Novosibirsk630090Russia Geophysical Laboratory Carnegie Institution for ScienceWashingtonDC20015USA Novosibirsk State University Pirogova st.2Novosibirsk630090Russia Geodynamic Research Center Ehime UniversityMatsuyamaEhime790-8577Japan Center for Advanced Radiation Sources University of ChicagoChicagoIL60637USA

The fate of subducted carbonates in the lower mantle and at the core-mantle boundary was modelled via experiments in the MgCO3-Fe^0 system at 70-150 GPa and 800-2600 Kin a laser-heated diamond anvil *** in situ synchrotro n X-ray diffraction and ex situ transmission electron microscopy we show that the reduction of Mg-carbonate can be exemplified by:6 MgCO3+19 Fe=8 FeO+10(Mg0.6Fe^0.4)O+Fe7 C3+3 *** presented results suggest that the interaction of carbonates with Fe^0 or Fe^0-bearing rocks can produce Fe-carbide and diamond,which can accumulate in the D"region,depending on its carbon to Fe *** to the sluggish kinetics of the transformation,diamond can remain metastable at the core-mantle boundary(CMB)unless it is in a direct contact with *** addition,it can be remobilized by redox melting accompanying the generation of mantle plumes.

关键词： Deep carbon cycle Carbonate Carbide High pressure Redox reaction

When water meets iron at Earth's core-mantle boundary

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National Science Review 2017年第6期4卷 870-878页

作者： Ho-Kwang Mao Qingyang Hu Liuxiang Yang Jin Liu Duck Young Kim Yue Meng Li Zhang vitali B.prakapenka Wenge Yang Wendy L.Mao Center for High Pressure Science and Technology Advanced Research Geophysical Laboratory Carnegie Institution Department of Geological Sciences Stanford University High Pressure Collaborative Access Team(HPCAT) Geophysical Laboratory Carnegie Institution Center for Advanced Radiation Sources University of Chicago

Hydrous minerals in subducted crust can transport large amounts of water into Earth’s deep mantle. Our laboratory experiments revealed the surprising pressure-induced chemistry that, when water meets iron at the core-mantle boundary, they react to form an interlayer with an extremely oxygen-rich form of iron, iron dioxide, together with iron hydride. Hydrogen in the layer will escape upon further heating and rise to the crust, sustaining the water cycle. With water supplied by the subducting slabs meeting the nearly inexhaustible iron source in the core, an oxygen-rich layer would cumulate and thicken, leading to major global consequences in our planet. The seismic signature of the D″ layer may echo the chemical complexity of this layer. Over the course of geological time, the enormous oxygen reservoir accumulating between the mantle and core may have eventually reached a critical eruption point. Very large-scale oxygen eruptions could possibly cause major activities in the mantle convection and leave evidence such as the rifting of supercontinents and the Great Oxidation Event.

关键词： high pressure core-mantle boundary water and iron

FeH_(x)的稳定性以及氢在地球核-幔边界的传输

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Science Bulletin 2023年第14期68卷 1567-1573,M0004页

作者：何宇 Duck Young Kim Viktor V.Struzhkin Zachary M.Geballe vitali prakapenka 毛河光 Key Laboratory of High-Temperature and High-Pressure Study of the Earth’s Interior Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Center for High Pressure Science and Technology Advanced Research Shanghai 201203China Division of Advanced Nuclear Engineering Pohang University of Science and TechnologyPohang 37673Republic of Korea Geophysical Laboratory Carnegie InstitutionWashington DC 20015USA Center for Advanced Radiation Sources University of ChicagoChicago IL 60637USA

地球内部水和铁的反应可以生成铁-氢合金.研究铁-氢合金可以增进对地球内部氢传输的认知.我们通过高压实验和第一性原理计算的方法,对高温高压下具有面心立方结构(fcc)FeH_(x)(x≤1)的相稳定性、密度、氢的输运性质和熔点进行了系统研究... 详细信息

地球内部水和铁的反应可以生成铁-氢合金.研究铁-氢合金可以增进对地球内部氢传输的认知.我们通过高压实验和第一性原理计算的方法,对高温高压下具有面心立方结构(fcc)FeH_(x)(x≤1)的相稳定性、密度、氢的输运性质和熔点进行了系统研究,证实了FeH_(x)在165 GPa时的稳定性.通过高温的分子动力学模拟,发现FeH_(x)在下地幔温压下转变为超离子态.在超离子态FeH_(x)中,氢离子快速扩散表现出类似流体的性质,扩散系数高达3.710^(-4)cm~2s^(-1).与超离子态冰类似,氢离子的快速扩散可以导致体系的熵增,使其的熔化温度增加.FeH_(x)可以将氢从地幔传输到外地核,使得外核成为H的潜在储库,并在核-幔边界上方留下了富氧的块状结构.

关键词：离子态第一性原理计算氢离子相稳定性地球内部熔化温度高压实验分子动力学模拟

Superconductivity in La and Y hydrides: Remaining questions to experiment and theory

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Matter and Radiation at Extremes 2020年第2期5卷 62-72页

作者： Viktor Struzhkin Bing Li Cheng Ji Xiao-Jia Chen vitali prakapenka Eran Greenberg Ivan Troyan Alexander Gavriliuk Ho-kwang Mao Center for High Pressure Science and Technology Advanced Research ShanghaiChina Geophysical Laboratory Carnegie Institution of WashingtonWashingtonDC 20015USA Center for Advanced Radiation Sources The University of Chicago5640 South Ellis AvenueChicagoIllinois 60637USA Federal Scientific Research Center Crystallography and Photonics Russian Academy of Sciences59 Leninskii Pr-tMoscow 119333Russia Institute for Nuclear Research Russian Academy of SciencesMoscowTroitsk 108840Russia

Recent reports of the superconductivity in hydrides of two different families(covalent lattice,as in SH3 and clathrate-type H-cages containing La and Y atoms,as in LaH10 and YH6)have revealed new families of high-Tc materials with Tc’s near room temperature *** findings confirm earlier expectations that hydrides may have very high Tc’s due to the fact that light H atoms have very high vibrational frequencies,leading to high Tc values within the conventional Bardeen–Cooper–Schrieffer phonon mechanism of ***,as is pointed out by Ashcroft,it is important to have the metallic hydrogen“alloyed”with the elements added to *** concept of a metallic alloy containing a high concentration of metal-like hydrogen atoms has been instrumental in finding new high-Tc *** new superhydride“roomtemperature”superconductors are stabilized only at very high pressures above 100 GPa,making the experimental search for their superconducting properties very *** will review the current experimental and theoretical results for LaH10−x and YH6−x superhydrides.

关键词： hydrides alloy metallic

Superconductivity above 70 K observed in lutetium polyhydrides

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Science China(Physics,Mechanics & Astronomy) 2023年第6期66卷 95-100页

作者： Zhiwen Li Xin He Changling Zhang Ke Lu Baosen Min Jun Zhang Sijia Zhang Jianfa Zhao Luchuan Shi Yi Peng Shaomin Feng Zheng Deng Jing Song Qingqing Liu Xiancheng Wang Richeng Yu Luhong Wang Yingzhe Li Jay D.Bass vitali prakapenka Stella Chariton Haozhe Liu Changqing Jin Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing100190China Songshan Lake Materials Laboratory Dongguan523808China Shanghai Advanced Research in Physical Sciences Shanghai201203China Department of Geology University of Illinois at Urbana ChampaignUrbana61801USA Center for Advanced Radiations Sources University of ChicagoChicago60637USA Center for High Pressure Science&Technology Advanced Research Beijing100094China

The binary polyhydrides of heavy rare earth lutetium that shares a similar valence electron configuration to lanthanum have been experimentally discovered to be *** lutetium polyhydrides were successfully synthesized at high pressure and high temperature conditions using a diamond anvil cell in combinations with the in-situ high pressure laser heating *** resistance measurements as a function of temperature were performed at the same pressure of synthesis in order to study the transitions of superconductivity(SC).The superconducting transition with a maximum onset temperature(Tc)71 K was observed at pressure of 218 GPa in the *** Tcdecreased to 65 K when pressure was at 181 *** the evolution of SC at applied magnetic fields,the upper critical field at zero temperatureμ0Hc2(0)was obtained to be~36 *** in-situ high pressure X-ray diffraction experiments imply that the high TcSC should arise from the Lu4H23phase with Pm3n symmetry that forms a new type of hydrogen cage framework different from those reported for previous light rare earth polyhydride superconductors.

关键词： lutetium polyhydrides superconductors at high pressures high pressure synthesis

Chemistry and P-V-T equation of state of FeOH at the base of Earth’s lower mantle and their geophysical implications

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Science Bulletin 2021年第19期66卷 1954-1958,M0003页

作者： Ruilian Tang Jin Liu Duck Young Kim Ho-Kwang Mao Qingyang Hu Bin Yang Yan Li Chris J.Pickard Richard J.Needs Yu He Haozhe Liu vitali B.prakapenka Yue Meng Jinyuan Yan Center for High Pressure Science and Technology Advanced Research Changchun 130012China School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China Department of Materials Science and Metallurgy University of CambridgeCambridge CB30FSUK Advanced Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Theory of Condensed Matter Group Cavendish LaboratoryCambridge CB30HEUK Key Laboratory of High-Temperature and High-Pressure Study of the Earth’s Interior Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Center for Advanced Radiation Sources University of ChicagoChicago IL 60439USA X-ray Science Division Argonne National LaboratoryArgonne IL 60439USA Material Science Division Lawrence Berkeley National LaboratoryBerkeley CA 94720USA CAS Center for Excellence in Deep Earth Science Guangzhou 510640China

The hydrogen-absorbing ability of a mantle mineral in its structure determines the capacity of the water reservoirs hosted by the mineral. Water reservoirs at the base of Earth’s mantle directly influence the fate of water brought down by slab subduction and the seismic heterogeneity such as ultralow-velocity zones(ULVZs)at the core-mantle boundary. Pyrite-Fe O2 Hx(0≤x ≤1) presents a possibility of such reservoirs in the deep mantle [1–3].

关键词：地球科学研究地球深部地球物理核幔边界同步辐射X射线衍射弹性性质下地幔化学组分

Phase Stability and Thermal Equation of State of δ-AlOOH: Implication for Water Transportation to the Deep Lower Mantle

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Phase Stability and Thermal Equation of State of δ-AlOOH: I...

Elasticity of Single-Crystal Fe-Bearing Diopside at High-Pressure Conditions

2018年中国地球科学联合学术年会

作者：段云飞孙宁宇汪思衡李新阳 vitali B.prakapenka 毛竹中国科学技术大学地球与空间科学学院美国阿贡国家实验室先进光源中心

The hydrous minerals in the subduction slab play a critical role in water transportation to the deep earth. As slab subducts, most hydrous minerals decompose at shallow depth, whereas a few hydrous minerals, such as phase D, phase H, and δ-AlOOH,may survive and keep stable to the relevant pressure-temperature (P-T) conditions of the

关键词： AlOOH Phase Stability and Thermal Equation of State of Implication for Water Transportation to the Deep Lower Mantle

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Elasticity of Single-Crystal Fe-Bearing Diopside at High-Pre...

中国矿物岩石地球化学学会第17届学术年会

作者：范大伟 Suyu Fu Chang Lu Jingui Xu Yanyao Zhang Sergey N.Tkachev vitali B.prakapenka Jungfu Lin Key Laboratory of High Temperature and High Pressure Study of the Earth's Interior Institute of GeochemistryChinese Academy of Sciences Department of Geological Sciences Jackson School of GeosciencesThe University of Texas at Austin Center for Advanced Radiation Sources University of Chicago

The monoclinic mineral diopside (CaMgSiO) is the calcium end member of Ca-rich clinopyroxene in the uppermost mantle. It is an important mineral component in pyrolite model,and is believed to be one of the most abunda...

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金和铂在高压富水条件下的化学活性的研究

金和铂在高压富水条件下的化学活性的研究