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Journal Articles

Design and performance of high-pressure PLANET beamline at pulsed neutron source at J-PARC

Hattori, Takanori; Sano, Asami; Arima, Hiroshi*; Komatsu, Kazuki*; Yamada, Akihiro*; Inamura, Yasuhiro; Nakatani, Takeshi; Seto, Yusuke*; Nagai, Takaya*; Utsumi, Wataru; et al.

Nuclear Instruments and Methods in Physics Research A, 780, p.55 - 67, 2015/04

 Times Cited Count:40 Percentile:1.21(Instruments & Instrumentation)

PLANET is a time-of-flight (ToF) neutron beamline dedicated to high-pressure and high-temperature experiments. The large six-axis multi-anvil high-pressure press designed for ToF neutron diffraction experiments enables routine data collection at high pressures and high temperatures up to 10 GPa and 2000 K, respectively. To obtain clean data, the beamline is equipped with the incident slits and receiving collimators to eliminate parasitic scattering from the high-pressure cell assembly. The high performance of the diffractometer for the resolution ($$Delta$$ $$d$$/$$d$$ $$sim$$ 0.6%) and the accessible $$d$$-spacing range (0.2-8.4 ${AA}$) together with low-parasitic scattering characteristics enables precise structure determination of crystals and liquids under high pressure and temperature conditions.

Journal Articles

Crystal structure and nuclear density distribution of LiCo$$_{1/3}$$Ni$$_{1/3}$$Mn$$_{1/3}$$O$$_{2}$$ analyzed by Rietveld/maximum entropy method

Igawa, Naoki; Taguchi, Tomitsugu; Fukazawa, Hiroshi; Yamauchi, Hiroki; Utsumi, Wataru

Journal of the American Ceramic Society, 93(8), p.2144 - 2146, 2010/08

 Times Cited Count:12 Percentile:39.15(Materials Science, Ceramics)

The neutron powder diffraction measurement of LiCo$$_{1/3}$$Ni$$_{1/3}$$Mn$$_{1/3}$$O$$_{2}$$ was carried out and the crystal structure and scattering density distribution were analyzed by Rietveld refinement and the maximum entropy method to estimate the Li diffusing pathway. Rietveld refinement showed that the structure was basically the same as LiCoO$$_{2}$$: a ${it R}$-3${it m}$ space group, with Li and O mainly occupying the 3${it a}$ and 6${it c}$ sites, and Co, Ni and Mn randomly occupying the 3${it b}$ site. Approximately 4% of the Li and Ni atoms exchanged their original sites (3${it a}$ and 3${it b}$) to occupy 3${it b}$ and 3${it a}$, respectively. Based on maximum entropy method analyses, we surmise that Li atoms moved on the (001), (003) and (00-3) planes and diffused through the 3${it a}$-9${it e}$-3${it a}$ sites on those planes.

Journal Articles

CO$$_{2}$$ motion in carbon dioxide deuterohydrate determined by applying maximum entropy method to neutron powder diffraction data

Igawa, Naoki; Taguchi, Tomitsugu; Hoshikawa, Akinori*; Fukazawa, Hiroshi; Yamauchi, Hiroki; Utsumi, Wataru; Ishii, Yoshinobu*

Journal of Physics and Chemistry of Solids, 71(6), p.899 - 905, 2010/06

 Times Cited Count:6 Percentile:66.25(Chemistry, Multidisciplinary)

Crystal structures of carbon dioxide deuterohydrate were studied by neutron powder diffraction at temperatures from 10 to 200 K. Maps of scattering length density distribution were obtained using a maximum entropy method, which clarified the motion of CO$$_{2}$$ molecules in the hydrate. In small cages, the carbon atom of the CO$$_{2}$$ molecule is at the center of the cage, and the oxygen atoms of CO$$_{2}$$ revolve freely around the carbon atom. In large cages, the carbon atom also is at the center of the cage, but the oxygen atoms tend to revolve around the carbon atom along the plane parallel to the hexagonal facets of the cage.

Journal Articles

A Cubic-anvil high-pressure device for pulsed neutron powder diffraction

Abe, Jun; Arakawa, Masashi*; Hattori, Takanori; Arima, Hiroshi; Kagi, Hiroyuki; Komatsu, Kazuki*; Sano, Asami; Uwatoko, Yoshiya*; Matsubayashi, Kazuyuki*; Harjo, S.; et al.

Review of Scientific Instruments, 81(4), p.043910_1 - 043910_5, 2010/04

 Times Cited Count:6 Percentile:64.92(Instruments & Instrumentation)

A compact cubic-anvil high-pressure device was developed for in situ neutron powder diffraction studies. In this device, a cubic shaped pressure medium is compressed by six anvils, and neutron beam pass through gaps between the anvils. The first high-pressure experiment using this device was conducted at J-PARC and clearly showed the neutron diffraction patterns of Pb. Combining the cubic-anvil high-pressure device with a pulsed neutron source will prove to be a useful tool for neutron diffraction experiments.

Journal Articles

High pressure experiments with the engineering materials diffractometer (BL-19) at J-PARC

Abe, Jun; Hattori, Takanori; Komatsu, Kazuki*; Arima, Hiroshi; Arakawa, Masashi*; Sano, Asami; Kagi, Hiroyuki; Harjo, S.; Ito, Takayoshi; Moriai, Atsushi; et al.

Journal of Physics; Conference Series, 215, p.012023_1 - 012023_6, 2010/03

 Times Cited Count:4 Percentile:15.48

A high-intensity proton accelerator facility named J-PARC has been constructed, and the first neutron beam at J-PARC/MLF was extracted in May of 2008, and user-operation commenced in December of the year. The fist feasibility test of high-pressure neutron experiments were performed with the engineering materials diffractometer "TAKUMI". As results, diffraction profiles of sample embedded in high-pressure devices were obtained. Therefore, it was confirmed that in situ high-pressure neutron diffraction was feasible with the engineering materials diffractometer "TAKUMI".

Journal Articles

Designing PLANET; Neutron beamline for high-pressure material science at J-PARC

Arima, Hiroshi; Hattori, Takanori; Komatsu, Kazuki*; Abe, Jun; Utsumi, Wataru; Kagi, Hiroyuki*; Suzuki, Akio*; Suzuya, Kentaro; Kamiyama, Takashi; Arai, Masatoshi; et al.

Journal of Physics; Conference Series, 215(1), p.012025_1 - 012025_6, 2010/03

The powder diffractometer dedicated to high-pressure experiments (PLANET) is now being constructed on BL11 at the spallation neutron source of J-PARC. PLANET aims to study structures of hydrogen-bearing materials including dense hydrous minerals of the Earth's deep interior, magmas and light element liquids. The instrument will realize diffraction and radiography experiments for powder and liquid/glass samples at high pressures up to 20 GPa and 2000 K. It covers d spacing from 0.2 ${AA}$ to 4.1 ${AA}$ at 90$$^{circ}$$ bank within the first frame.

Journal Articles

Designing PLANET; Neutron beamline for high-pressure material science at J-PARC

Arima, Hiroshi*; Hattori, Takanori; Komatsu, Kazuki*; Abe, Jun; Utsumi, Wataru; Kagi, Hiroyuki*; Suzuki, Akio*; Suzuya, Kentaro; Kamiyama, Takashi*; Arai, Masatoshi; et al.

Journal of Physics; Conference Series, 215(1), p.012025_1 - 012025_6, 2010/03

 Times Cited Count:12 Percentile:3.29

The powder diffractometer dedicated to high-pressure experiments (PLANET) is now being constructed on BL11 at the spallation neutron source of J-PARC. PLANET aims to study structures of hydrogen-bearing materials including dense hydrous minerals of the Earth's deep interior, magmas and light element liquids. The instrument will realize diffraction and radiography experiments for powder and liquid/glass samples at high pressures up to 20 GPa and 2000 K. It covers $$d$$ spacing from 0.2${AA}$ to 4.1${AA}$ at 90$$^{circ}$$ bank within the first frame. The design and performance of PLANET have been evaluated using Monte Carlo simulations.

Journal Articles

Design concept and the current construction state of J-PARC high-pressure neutron diffractometer PLANET

Hattori, Takanori; Arima, Hiroshi; Utsumi, Wataru

Hamon, 20(1), p.39 - 44, 2010/01

The new beamline dedicated to high-pressure studies, PLANET is now being constructed at BL11 in MLF/J-PARC. The design concept and the current construction state are introduced. The most characteristic feature of this beamline is a huge press with the maximum load of 1500 ton. The coupling this with the state of the art neuron techniques reveals hydrogen positions and its effects on the physical properties of materials and minerals at tens of gigapascals and a few thousand Kelvins. This opens the door to explore deep interior of the hydrous Earth and Planets.

Journal Articles

Neutron powder diffraction and difference maximum entropy method analysis of protium- and deuterium-dissolved BaSn$$_{0.5}$$In$$_{0.5}$$O$$_{2.75+alpha}$$

Nagasaki, Takanori*; Shiotani, Shinya*; Igawa, Naoki; Yoshino, Masahito*; Iwasaki, Kota*; Fukazawa, Hiroshi; Utsumi, Wataru

Journal of Solid State Chemistry, 182(10), p.2632 - 2639, 2009/10

 Times Cited Count:5 Percentile:77.63(Chemistry, Inorganic & Nuclear)

We propose a new method, a difference maximum entropy method (MEM) analysis of the neutron diffraction data, for revealing the detailed structure around hydrogen atoms in proton-conducting oxides. This MEM analysis uses the differences between the structure factors of protium- and deuterium-dissolved crystals. Simulations demonstrate that it not only provides the distribution of hydrogen atoms alone, but also improves the spatial resolution of MEM mapping around hydrogen atoms. Applied to actual diffraction data of protium- and deuterium-dissolved BaSn$$_{0.5}$$In$$_{0.5}$$O$$_{2.75+alpha}$$ at 9 K, difference MEM analysis reveals that O-D bonds mostly tilt towards the second nearest oxygen atoms, and that the distributions of deuterium and oxygen atoms are probably insignificant in interstitial regions.

Journal Articles

Strategy of high pressure research with neutron at J-PARC

Utsumi, Wataru

Koatsuryoku No Kagaku To Gijutsu, 19(1), p.10 - 14, 2009/03

User operation of J-PARC started in December of 2008. It is expected that high pressure material science and the investigation of the Earth's interior will greatly improve using the high flux pulse neutrons of J-PARC. In this article, I introduce the current status of neutron powder diffraction beamlines and our strategy of high pressure experiments.

Journal Articles

Neutron powder diffraction under high pressure at J-PARC

Utsumi, Wataru; Kagi, Hiroyuki*; Komatsu, Kazuki*; Arima, Hiroshi*; Nagai, Takaya*; Okuchi, Takuo*; Kamiyama, Takashi*; Uwatoko, Yoshiya*; Matsubayashi, Kazuyuki*; Yagi, Takehiko*

Nuclear Instruments and Methods in Physics Research A, 600(1), p.50 - 52, 2009/02

 Times Cited Count:11 Percentile:35.15(Instruments & Instrumentation)

The application of high pressure can induce dramatic changes in the physical properties of condensed matter. Diffraction experiments under high pressure provide precise structural information, which is fundamental to understand their origin. When in situ high pressure neutron diffraction becomes possible at J-PARC, further outstanding researches are expected such as crystal structure of hydrogen-bearing materials including hydrous minerals, order-disorder transitions of minerals, structure of light element liquid at high pressure, etc.. Conceptual designs of neutron optics and high pressure devices for J-PARC are introduced.

JAEA Reports

Development of asymmetric reflection-type germanium monochromator for neutron beam enhancement

Yamauchi, Hiroki; Ishii, Yoshinobu*; Igawa, Naoki; Fukazawa, Hiroshi; Utsumi, Wataru

JAEA-Research 2008-077, 28 Pages, 2008/10

JAEA-Research-2008-077.pdf:24.52MB

The neutron powder diffractometer, HRPD, can provide high-resolution data that meet the many users' needs until now. On the other hand, the demand of high-efficiency is growing in the recent years. In order to improve the source intensity and measurement efficiency, the authors tried to develop asymmetric reflection-type Ge monochromators. The mosaic crystals (20$$^prime$$ in the horizontal direction) were cut at an angle of 40 $$^circ$$ relative to the Ge,3,3,1 reflecting planes. The diffraction results of standard Si samples reveal that peak intensities by the asymmetric type are improved 1.2 times larger than those by the existing symmetric type, but integrated intensities are almost comparable each other. For mosaic crystals, asymmetric reflections in compression geometry intensify the current density, but reflectivity is always less than that in symmetric reflections, and thus the suppression of the reflectivity just cancels out the enhancement of the current density.

Journal Articles

Experimental constraints on the phase diagram of titanium metal

Zhang, J.*; Zhao, Y.*; Hixson, R. S.*; Gray III, G. T.*; Wang, L.*; Utsumi, Wataru; Saito, Hiroyuki; Hattori, Takanori

Journal of Physics and Chemistry of Solids, 69(10), p.2559 - 2563, 2008/10

 Times Cited Count:22 Percentile:30.92(Chemistry, Multidisciplinary)

Journal Articles

Thermal equations of state for titanium obtained by high pressure-temperature diffraction studies

Zhang, J.*; Zhao, Y.*; Hixson, R. S.*; Gray III, G. T.*; Wang, L.*; Utsumi, Wataru; Saito, Hiroyuki; Hattori, Takanori

Physical Review B, 78(5), p.054119_1 - 054119_7, 2008/08

 Times Cited Count:40 Percentile:17.03(Materials Science, Multidisciplinary)

Journal Articles

A High pressure experiment of powder neutron diffraction on the HRPD at JRR-3

Komatsu, Kazuki*; Arima, Hiroshi*; Kagi, Hiroyuki*; Okuchi, Takuo*; Sasaki, Shigeo*; Yamauchi, Hiroki; Fukazawa, Hiroshi; Igawa, Naoki; Utsumi, Wataru; Kamiyama, Takashi*

Koatsuryoku No Kagaku To Gijutsu, 18(2), p.170 - 172, 2008/05

In this short communication, we report neutron diffractions under high pressure from lead powder in a Paris-Edinburgh cell at the High Resolution Powder Diffractometer (HRPD) installed at JRR-3, Ibaraki, Japan. This is the kick-off experiment in Japan as a high pressure powder diffraction study using reactor neutron source.

Journal Articles

Solid-phase grain growth of In$$_{2}$$O$$_{3}$$ at high pressures and temperatures

Saito, Hiroyuki; Utsumi, Wataru; Aoki, Katsutoshi

Journal of Crystal Growth, 310(7-9), p.2295 - 2297, 2008/04

 Times Cited Count:8 Percentile:35.91(Crystallography)

Journal Articles

Decomposition of InN at high pressures and temperatures and its thermal instability at ambient conditions

Saito, Hiroyuki; Utsumi, Wataru; Aoki, Katsutoshi

Journal of Crystal Growth, 310(2), p.473 - 476, 2008/01

 Times Cited Count:12 Percentile:26.64(Crystallography)

Journal Articles

High-pressure structural study on amorphous materials using cBN anvils

Hattori, Takanori; Saito, Hiroyuki; Kaneko, Hiroshi; Okajima, Yuka; Aoki, Katsutoshi; Utsumi, Wataru

KEK Proceedings 2007-7, p.56 - 60, 2007/12

We introduce high-pressure study on amorphous materials using a multi-anvils press equipped with the X-ray transparent cBN anvils. First, we mention merits of the angle-dispersive X-ray diffraction system compared with the conventional energy-dispersive system. Next, we show the results of the verification of the high-pressure formation of the elemental bulk metallic glass as an example. Finally, the characteristics of X-ray absorption are shown both for the combinational sintered diamond anvils and the presently used cBN anvils.

Journal Articles

Molecular-network-ionic structure transitions in liquid AlCl$$_{3}$$ and ZnCl$$_{2}$$ halogenides under pressure

Brazhkin, V. V.*; Lyapin, A. G.*; Popova, S. V.*; Katayama, Yoshinori; Saito, Hiroyuki; Utsumi, Wataru

Journal of Physics; Condensed Matter, 19(24), p.246104_1 - 246104_10, 2007/06

 Times Cited Count:22 Percentile:30.78(Physics, Condensed Matter)

Liquid AlCl$$_{3}$$ and ZnCl$$_{2}$$ halogenides are studied by ${it in-situ}$ high-pressure high-temperature X-ray diffraction measurements. These halogenides have a quasi-molecular network structure in liquid state at normal pressure. They are intermediate between pure covalent and ionic melts. The present study is indicative of a rapid and strong breakdown of an intermediate range order in a tetrahedral network of melts for the initial pressure range and points to rather sharp transitions in liquids with the formation of a short-range order structure similar to ionic melt structures. Such a two-stage structural transformation under pressure is the general feature for a wide class of simple melts, including most of the pseudo-covalent halogenides.

Journal Articles

Does bulk metallic glass of elemental Zr and Ti exist ?; Verification of the high-pressure formation of amorphous Zr and Ti

Hattori, Takanori; Saito, Hiroyuki; Aoki, Katsutoshi; Kaneko, Hiroshi; Okajima, Yuka; Utsumi, Wataru

Nippon Kessho Gakkai-Shi, 49(3), p.179 - 185, 2007/06

The high-pressure formation of the bulk metallic glass of elemental Zr and Ti, which has been recently reported, is verified by a newly developed angle dispersive X-ray diffraction (ADX) system using a large volume multi-anvil apparatus equipped with X-ray transparent anvils. The ADX data revealed that Zr and Ti remain as a crystalline form at high-pressure and temperature condition where the amorphization has been reported. The misinterpretation in the previous papers is attributed to the anomalous rapid grain growth that is related to the characteristic lattice dynamic and the resulting anomalously fast self diffusion in the high-temperature phases of Zr and Ti.

177 (Records 1-20 displayed on this page)