Faculty Profiles - Ishii Takayuki

Papers - Ishii Takayuki

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High‐Pressure Elasticity of δ‐(Al,Fe)OOH Single Crystals and Seismic Detectability of Hydrous MORB in the Shallow Lower Mantle Reviewed

Niccolò Satta, Giacomo Criniti, Alexander Kurnosov, Tiziana Boffa Ballaran, Takayuki Ishii, Hauke Marquardt

Geophysical Research Letters 48 ( 23 ) 2021.12

Synthesis of paracrystalline diamond Reviewed

Hu Tang, Xiaohong Yuan, Yong Cheng, Hongzhan Fei, Fuyang Liu, Tao Liang, Zhidan Zeng, Takayuki Ishii, Ming-Sheng Wang, Tomoo Katsura, Howard Sheng, Huiyang Gou

Nature 599 ( 7886 ) 605 - 610 2021.11

A simplified rapid-quench multi-anvil technique Reviewed

Dmitry Bondar, Hongzhan Fei, Anthony C. Withers, Takayuki Ishii, Artem Chanyshev, Tomoo Katsura

Review of Scientific Instruments 92 ( 11 ) 113902 - 113902 2021.11

Spectroscopic evidence for the Fe3+ spin transition in iron-bearing δ-AlOOH at high pressure Reviewed

Xiaowan Su, Chaoshuai Zhao, Liangxu Xu, Chaojia Lv, Xitong Song, Takayuki Ishii, Yuming Xiao, Paul Chow, Qiang Sun, Jin Liu

American Mineralogist 106 ( 11 ) 1709 - 1716 2021.11

Publishing type：Research paper (scientific journal) Publisher：Mineralogical Society of America

Abstract

δ-AlOOH has emerged as a promising candidate for water storage in the lower mantle and could have delivered water into the bottom of the mantle. To date, it still remains unclear how the presence of iron affects its elastic, rheological, vibrational, and transport properties, especially across the spin crossover. Here, we conducted high-pressure X-ray emission spectroscopy experiments on a δ-(Al0.85Fe0.15) OOH sample up to 53 GPa using silicone oil as the pressure transmitting medium in a diamond-anvil cell. We also carried out laser Raman measurements on δ-(Al0.85Fe0.15)OOH and δ-(Al0.52Fe0.48)OOH up to 57 and 62 GPa, respectively, using neon as the pressure-transmitting medium. Evolution of Raman spectra of δ-(Al0.85Fe0.15)OOH with pressure shows two new bands at 226 and 632 cm−1 at 6.0 GPa, in agreement with the transition from an ordered (P21nm) to a disordered hydrogen bonding structure (Pnnm) for δ-AlOOH. Similarly, the two new Raman bands at 155 and 539 cm−1 appear in δ-(Al0.52Fe0.48)OOH between 8.5 and 15.8 GPa, indicating that the incorporation of 48 mol% FeOOH could postpone the order-disorder transition upon compression. On the other hand, the satellite peak (Kβ′) intensity of δ-(Al0.85Fe0.15)OOH starts to decrease at ~30 GPa and it disappears completely at 42 GPa. That is, δ-(Al0.85Fe0.15)OOH undergoes a gradual electronic spin-pairing transition at 30–42 GPa. Furthermore, the pressure dependence of Raman shifts of δ-(Al0.85Fe0.15)OOH discontinuously decreases at 32–37 GPa, suggesting that the improved hydrostaticity by the use of neon pressure medium could lead to a relatively narrow spin crossover. Notably, the pressure dependence of Raman shifts and optical color of δ-(Al0.52Fe0.48)OOH dramatically change at 41–45 GPa, suggesting that it probably undergoes a relatively sharp spin transition in the neon pressure medium. Together with literature data on the solid solutions between δ-AlOOH and ε-FeOOH, we found that the onset pressure of the spin transition in δ-(Al,Fe)OOH increases with increasing FeOOH content. These results shed new insights into the effects of iron on the structural evolution and vibrational properties of δ-AlOOH. The presence of FeOOH in δ-AlOOH can substantially influence its high-pressure behavior and stability at the deep mantle conditions and play an important role in the deep-water cycle.

DOI： 10.2138/am-2021-7541

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In situ high-pressure nuclear magnetic resonance crystallography in one and two dimensions Reviewed

Thomas Meier, Alena Aslandukova, Florian Trybel, Dominique Laniel, Takayuki Ishii, Saiana Khandarkhaeva, Natalia Dubrovinskaia, Leonid Dubrovinsky

Matter and Radiation at Extremes 6 ( 6 ) 068402 - 068402 2021.11

The elastic properties and anisotropic behavior of MgSiO3 akimotoite at transition zone pressures Reviewed

Nicki C. Siersch, Alexander Kurnosov, Giacomo Criniti, Takayuki Ishii, Tiziana Boffa Ballaran, Daniel J. Frost

Physics of the Earth and Planetary Interiors 320 106786 - 106786 2021.11

Simultaneous generation of ultrahigh pressure and temperature to 50 GPa and 3300 K in multi-anvil apparatus Reviewed

Longjian Xie, Artem Chanyshev, Takayuki Ishii, Dmitry Bondar, Keisuke Nishida, Zhen Chen, Shrikant Bhat, Robert Farla, Yuji Higo, Yoshinori Tange, Xiaowan Su, BingMin Yan, Shuailin Ma, Tomoo Katsura

Review of Scientific Instruments 92 ( 10 ) 103902 - 103902 2021.10

Determination of phase relations of the olivine–ahrensite transition in the Mg2SiO4–Fe2SiO4 system at 1740 K using modern multi-anvil techniques Reviewed

Artem Chanyshev, Dmitry Bondar, Hongzhan Fei, Narangoo Purevjav, Takayuki Ishii, Keisuke Nishida, Shrikant Bhat, Robert Farla, Tomoo Katsura

Contributions to Mineralogy and Petrology 176 ( 10 ) 2021.9

Publishing type：Research paper (scientific journal) Publisher：Springer Science and Business Media LLC

Abstract

The phase relations of iron-rich olivine and its high-pressure polymorphs are important for planetary science and meteoritics because these minerals are the main constituents of terrestrial mantles and meteorites. The olivine–ahrensite binary loop was previously determined by thermochemical calculations in combination with high-pressure experiments; however, the transition pressures contained significant uncertainties. Here we determined the binary loop of the olivine–ahrensite transition in the (Mg,Fe)₂SiO₄ system at 1740 K in the pressure range of 7.5–11.2 GPa using a multi-anvil apparatus with the pressure determined using in situ X-ray diffraction, compositional analysis of quenched run products, and thermochemical calculation. Based on the determined binary loop, a user-friendly software was developed to calculate pressure from the coexisting olivine and ahrensite compositions. The software is used to estimate the shock conditions of several L6-type chondrites. The obtained olivine–ahrensite phase relations can also be applied for precise in-house multi-anvil pressure calibration at high temperatures.

DOI： 10.1007/s00410-021-01829-x

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Other Link： https://link.springer.com/article/10.1007/s00410-021-01829-x/fulltext.html

Vibrational anisotropy of δ-(Al,Fe)OOH single crystals as probed by nuclear resonant inelastic X-ray scattering Reviewed

Johannes Buchen, Wolfgang Sturhahn, Takayuki Ishii, Jennifer M. Jackson

European Journal of Mineralogy 33 ( 4 ) 485 - 502 2021.8

Publishing type：Research paper (scientific journal) Publisher：Copernicus GmbH

Abstract. The formation of high-pressure oxyhydroxide phases spanned by the components AlOOH–FeOOH–MgSiO2(OH)2 in experiments suggests their capability to retain hydrogen in Earth's lower mantle. Understanding the vibrational properties of high-pressure phases provides the basis for assessing their thermal properties, which are required to compute phase diagrams and physical properties. Vibrational properties can be highly anisotropic, in particular for materials with crystal structures of low symmetry that contain directed structural groups or components. We used nuclear resonant inelastic X-ray scattering (NRIXS) to probe lattice vibrations that involve motions of 57Fe atoms in δ-(Al0.87Fe0.13)OOH single crystals. From the recorded single-crystal NRIXS spectra, we calculated projections of the partial phonon density of states along different crystallographic directions. To describe the anisotropy of central vibrational properties, we define and derive tensors for the partial phonon density of states, the Lamb–Mössbauer factor, the mean kinetic energy per vibrational mode, and the mean force constant of 57Fe atoms. We further show how the anisotropy of the Lamb–Mössbauer factor can be translated into anisotropic displacement parameters for 57Fe atoms and relate our findings on vibrational anisotropy to the crystal structure of δ-(Al,Fe)OOH. As a potential application of single-crystal NRIXS at high pressures, we discuss the evaluation of anisotropic thermal stresses in the context of elastic geobarometry for mineral inclusions. Our results on single crystals of δ-(Al,Fe)OOH demonstrate the sensitivity of NRIXS to vibrational anisotropy and provide an in-depth description of the vibrational behavior of Fe3+ cations in a crystal structure that may motivate future applications of NRIXS to study anisotropic vibrational properties of minerals.

DOI： 10.5194/ejm-33-485-2021

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P-V-Tmeasurements of Fe3C to 117 GPa and 2100 K: Implications for stability of Fe3C phase at core conditions Reviewed

Chris McGuire, Tetsuya Komabayashi, Samuel Thompson, Geoffrey Bromiley, Takayuki Ishii, Eran Greenberg, Vitali B. Prakapenka

American Mineralogist 106 ( 8 ) 1349 - 1359 2021.8

Publishing type：Research paper (scientific journal) Publisher：Mineralogical Society of America

Abstract

We report the thermal Equation of State (EoS) of the non-magnetic Fe3C phase based on in situ X-ray diffraction (XRD) experiments to 117 GPa and 2100 K. High-pressure and temperature unit-cell volume measurements of Fe3C were conducted in a laser-heated diamond-anvil cell. Our pressure-volume-temperature (P-V-T) data together with existing data were fit to the Vinet equation of state with the Mie-Grüneisen-Debye thermal pressure model, yielding V0 = 151.6(12) Å3, K0 = 232(24) GPa, K0′= 5.09(46), γ0 = 2.3(3), and q = 3.4 (9) with θ0 = 407 K (fixed). The high-T data were also fit to the thermal pressure model with a constant αKT term, PTh = αKT(ΔT), and there is no observable pressure or temperature dependence, which implies minor contributions from the anharmonic and electronic terms. Using the established EoS for Fe3C, we made thermodynamic calculations on the P-T locations of the breakdown reaction of Fe3C into Fe7C3 and Fe. The reaction is located at 87 GPa and 300 K and 251 GPa and 3000 K. An invariant point occurs where Fe, Fe3C, Fe7C3, and liquid are stable, which places constraints on the liquidus temperature of the outer core, namely inner core crystallization temperature, as the inner core would be comprised by the liquidus phase. Two possible P-T locations for the invariant point were predicted from existing experimental data and the reaction calculated in this study. The two models result in different liquidus “phases” at the outer core-inner core boundary pressure: Fe3C at 5300 K and Fe7C3 at 3700 K. The Fe7C3 inner core can account for the density, as observed by seismology, while the Fe3C inner core cannot. The relevance of the system Fe-C to Earth’s core can be resolved by constructing a thermodynamic model for melting relations under core conditions as the two models predict very different liquidus temperatures.

DOI： 10.2138/am-2021-7581

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High-pressure syntheses and crystal structure analyses of a new low-density CaFe2O4-related and CaTi2O4-type MgAl2O4 phases Reviewed

Takayuki Ishii, Giacomo Criniti, Elena Bykova, Leonid Dubrovinsky, Tomoo Katsura, Hidekazu Arii, Hiroshi Kojitani, Masaki Akaogi

American Mineralogist 106 ( 7 ) 1105 - 1112 2021.7

Authorship：Lead author,　Corresponding author Publishing type：Research paper (scientific journal) Publisher：Mineralogical Society of America

Abstract

Three single crystals of CaTi2O4 (CT)-type, CaFe2O4 (CF)-type, and new low-density CaFe2O4 (LD-CF) related MgAl2O4 were synthesized at 27 GPa and 2500 °C and also CT-type MgAl2O4 at 45 GPa and 1727 °C using conventional and advanced multi-anvil technologies, respectively. The structures of CT-type and LD-CF related MgAl2O4 were analyzed by single-crystal X-ray diffraction. The lattice parameters of the CT-type phases synthesized at 27 and 45 GPa were a = 2.7903(4), b = 9.2132(10), and c = 9.3968(12) Å, and a = 2.7982(6), b = 9.2532(15), and c = 9.4461(16) Å, respectively, (Z = 4, space group: Cmcm) at ambient conditions. This phase has an AlO6 octahedral site and an MgO8 bicapped trigonal prism with two longer cation-oxygen bonds. The LD-CF related phase has a novel structure with orthorhombic symmetry (space group: Pnma), and lattice parameters of a = 9.207(2), b = 3.0118(6), and c = 9.739(2) Å (Z = 4). The structural framework comprises tunnel-shaped spaces constructed by edge- and corner-sharing of AlO6 and a 4+1 AlO5 trigonal bipyramid, in which MgO5 trigonal bipyramids are accommodated. The CF-type MgAl2O4 also has the same space group of Pnma but a slightly different atomic arrangement, with Mg and Al coordination numbers of 8 and 6, respectively. The LD-CF related phase has the lowest density of 3.50 g/cm3 among MgAl2O4 polymorphs, despite its high-pressure synthesis from the spinel-type phase (3.58 g/cm3), indicating that the LD-CF related phase formed via back-transformation from a high-pressure phase during the recovery. Combined with the previously determined phase relations, the phase transition between CF-and CT-type MgAl2O4 is expected to have a steep Clapeyron slope. Therefore, CT-type phase may be stable in basaltic- and continental-crust compositions at higher temperatures than the average mantle geotherm in the wide pressure range of the lower mantle. The LD-CF related phase could be found in shocked meteorites and used for estimating shock conditions.

DOI： 10.2138/am-2021-7619

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Dry metastable olivine and slab deformation in a wet subducting slab Reviewed

Takayuki Ishii, Eiji Ohtani

Nature Geoscience 14 ( 7 ) 526 - 530 2021.5

Effect of Water on Lattice Thermal Conductivity of Ringwoodite and Its Implications for the Thermal Evolution of Descending Slabs Reviewed

Enrico Marzotto, Wen‐Pin Hsieh, Takayuki Ishii, Keng‐Hsien Chao, Gregor J. Golabek, Marcel Thielmann, Eiji Ohtani

Geophysical Research Letters 47 ( 13 ) 2020.7

Discovery of New‐Structured Post‐Spinel MgFe ₂ O ₄ : Crystal Structure and High‐Pressure Phase Relations Reviewed

Takayuki Ishii, Nobuyoshi Miyajima, Ryosuke Sinmyo, Hiroshi Kojitani, Daisuke Mori, Yoshiyuki Inaguma, Masaki Akaogi

Geophysical Research Letters 47 ( 6 ) 2020.3

Spin Transition of Iron in δ‐(Al,Fe)OOH Induces Thermal Anomalies in Earth's Lower Mantle Reviewed

Wen‐Pin Hsieh, Takayuki Ishii, Keng‐Hsien Chao, Jun Tsuchiya, Frédéric Deschamps, Eiji Ohtani

Geophysical Research Letters 47 ( 4 ) 2020.2

Stability and Solubility of the FeAlO ₃ Component in Bridgmanite at Uppermost Lower Mantle Conditions Reviewed

Zhaodong Liu, Catherine McCammon, Biao Wang, Leonid Dubrovinsky, Takayuki Ishii, Dmitry Bondar, Ayano Nakajima, Yoshinori Tange, Yuji Higo, Tian Cui, Bingbing Liu, Tomoo Katsura

Journal of Geophysical Research: Solid Earth 125 ( 2 ) 2020.2

Development of High-Pressure Technology with Kawai-Type Multi-Anvil Presses and its Application to Geoscience Invited Reviewed

Takayuki ISHII

The Review of High Pressure Science and Technology 30 ( 2 ) 156 - 165 2020

Crystal Structure of a Novel Fe-Mg Oxide and Deep Earth Science Invited Reviewed

Takayuki ISHII

Nihon Kessho Gakkaishi 61 ( 4 ) 205 - 206 2019.12

Sharp 660-km discontinuity controlled by extremely narrow binary post-spinel transition Reviewed

Takayuki Ishii, Rong Huang, Robert Myhill, Hongzhan Fei, Iuliia Koemets, Zhaodong Liu, Fumiya Maeda, Liang Yuan, Lin Wang, Dmitry Druzhbin, Takafumi Yamamoto, Shrikant Bhat, Robert Farla, Takaaki Kawazoe, Noriyoshi Tsujino, Eleonora Kulik, Yuji Higo, Yoshinori Tange, Tomoo Katsura

Nature Geoscience 12 ( 10 ) 869 - 872 2019.9

The stability of Fe5O6 and Fe4O5 at high pressure and temperature Reviewed

Koutaro Hikosaka, Ryosuke Sinmyo, Kei Hirose, Takayuki Ishii, Yasuo Ohishi

American Mineralogist 104 ( 9 ) 1356 - 1359 2019.9

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Papers - Ishii Takayuki