A5027602966- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Magnetism in coordination complexes
- Organic and Molecular Conductors Research
- Lanthanide and Transition Metal Complexes
- Metal-Organic Frameworks: Synthesis and Applications
- Electron Spin Resonance Studies
- Polyoxometalates: Synthesis and Applications
- Magnetic properties of thin films
- Iron oxide chemistry and applications
- Magneto-Optical Properties and Applications
- Multiferroics and related materials
- Inorganic Chemistry and Materials
- Crystallography and molecular interactions
- Solid-state spectroscopy and crystallography
- Covalent Organic Framework Applications
- Porphyrin and Phthalocyanine Chemistry
- Metal complexes synthesis and properties
- Magnetic Properties and Synthesis of Ferrites
- Metamaterials and Metasurfaces Applications
- Transition Metal Oxide Nanomaterials
- Ferroelectric and Piezoelectric Materials
- Advanced NMR Techniques and Applications
- Thermal Expansion and Ionic Conductivity
- Fatty Acid Research and Health
The University of Tokyo
2015-2024
Bunkyo University
2009-2021
University of Toyama
2017
Sagami Women's University
2013
Tokyo University of Science
2010
We observed high proton conductivities of 1.2 x 10(-3) and 1.6 S cm(-1) on Co[Cr(CN)(6)](2/3).zH(2)O V[Cr(CN)(6)](2/3).zH(2)O, respectively, an interference effect between magnetic ordering ionic conduction below the phase transition temperature.
Abstract Iron(III) oxide shows a polymorphism, characteristic of existence phases with the same chemical composition but distinct crystal structures and, hence, physical properties. Four crystalline iron(III) have previously been identified: α-Fe 2 O 3 (hematite), β-Fe , γ-Fe (maghemite) and ε-Fe . All four easily undergo various phase transformations in response to heating or pressure treatment, usually forming hexagonal which is most thermodynamically stable Fe polymorph under ambient...
Abstract Development of nanometer-sized magnetic particles exhibiting a large coercive field ( H c ) is in high demand for densification recording. Herein, we report single-nanosize (i.e., less than ten nanometers across) hard ferrite. This ferrite composed ε-Fe 2 O 3 , with sufficiently value recording systems and remarkably anisotropy constant 7.7 × 10 6 erg cm −3 . For example, 8.2-nm nanoparticles have an 5.2 kOe at room temperature. A colloidal solution these possesses light orange...
Abstract Commonly available heat-storage materials cannot usually store the energy for a prolonged period. If solid material could conserve accumulated thermal energy, then its application potential is considerably widened. Here we report phase transition that can latent heat in wide temperature range, T <530 K and release on of pressure. This stripe-type lambda-trititanium pentoxide, λ-Ti 3 O 5 , which exhibits solid–solid to beta-trititanium β-Ti . The pressure conversion extremely...
The addition of chiral 2,2′-(2,6-pyridinediyl)bis(4-isopropyl-2-oxazoline) (iPr-Pybox) to a self-assembled CoII–[WV(CN)8] magnetic system gives two enantiomorphic cyano-bridged chains, {[CoII((S,S)-iPr-Pybox)(MeOH)]3[WV(CN)8]2·5.5MeOH·0.5H2O}n (1-SS) and {[CoII((R,R)-iPr-Pybox) (MeOH)]3[WV(CN)8]2·5.5MeOH·0.5H2O}n (1-RR). Both compounds crystallize with structure containing unique crossed arrangement one-dimensional chains that form microporous supramolecular network large channels (14.9 Å ×...
AimsAlthough dietary saturated fatty acids (SFA) are considered atherogenic, associations between SFAs intake and stroke coronary heart disease still debated. We sought to test the hypothesis that SFA is associated inversely with risk of its subtypes positively among Japanese, whose average lower than Westerners.
Light- or electromagnetic wave-responsive magnetism is an attractive issue in spin chemistry and optical materials science. Herein we show the magnetization reversal induced by visible-light pulsed laser ultrafast dynamic magnetooptical effect caused terahertz (THz) irradiation onto chemically synthesized magnetic films based on gallium–titanium–cobalt-substituted ε-Fe2O3 (GTC-ε-Fe2O3) nanoparticles. Visible-light switches sign of Faraday GTC-ε-Fe2O3 films. On other hand, irradiating film...
In the era of Big Data and Internet Things, data archiving is a key technology. From this viewpoint, magnetic recordings are drawing attention because they guarantee long-term storage. To archive an enormous amount data, further increase recording density necessary. Herein new methodology, "focused-millimeter-wave-assisted (F-MIMR)," proposed. test films based on epsilon iron oxide nanoparticles prepared focused-millimeter-wave generator constructed using terahertz (THz) light. Irradiating...
A void in the issue: one-step self-assembly of γ-Keggin sandwich-type silicotungstates with M2Zn2 (M=Co, Ni, Zn) tetranuclear cores and tetrabutylammonium cations gave porous ionic crystals. These crystals are hollow frameworks containing large voids (ca. 38×38×38 Å3, see picture, yellow), between which guest molecules can be exchanged through connecting channels. Detailed facts importance to specialist readers published as "Supporting Information". Such documents peer-reviewed, but not...
Magnetic ferrites are stable, sustainable, and economical. Consequently, they have been used in various fields. The development of large coercive field (large Hc) magnetic is a very important but challenging issue to accelerate the spread use expand practical applications. In this study, we prepared rhodium-substituted ε-iron oxide film observed remarkably Hc value 35 kOe at room temperature. This largest among date. Such large-Hc ferrite expected greatly application ferrites. Furthermore,...
Solid refrigerants exhibiting a caloric effect upon applying external stimuli are receiving attention as one of the next-generation refrigeration technologies. Herein, we report new inorganic refrigerant, rubidium cyano-bridged manganese-iron-cobalt ternary metal assembly (cyano-RbMnFeCo). Cyano-RbMnFeCo shows reversible barocaloric with large adiabatic temperature changes 74 K (from 57 °C to -17 °C) at 340 MPa, and 85 88 3 560 MPa. Such have yet be reported among effects in solid-solid...
To solve the deterioration of water resource environment, on-site production technologies have garnered attention. Here, we demonstrate example pressure-induced using a copper–chromium Prussian blue analog...
In this work, we prepared a three-dimensional vanadium octacyanoniobate-based magnet, K(0.10)V(II)(0.54)V(III)(1.24)[Nb(IV)(CN)(8)].(SO(4))(0.45).6.8H(2)O. This compound exhibits ferrimagnetism with Curie temperature of 138 K, in which the sublattice magnetizations V(II) (S = (3)/(2)) and V(III) 1) are antiparallelly ordered to that Nb(IV) (1)/(2)). The estimated superexchange interaction constants V(II)-Nb(IV) V(III)-Nb(IV) -51 -25 cm(-1), respectively.
The phase transition between gamma-trititanium-pentoxide (γ-Ti3O5) and delta-trititanium-pentoxide (δ-Ti3O5) was clarified from both experimental theoretical viewpoints. With decreasing temperature, the monoclinic I2/c crystal structure of γ-Ti3O5 found to switch a P2/a δ-Ti3O5 due lowering symmetry. Electrical conductivity (σ) measurement shows that behaves like metallic conductor with σ value 4.7 S cm–1 at 320 K, while semiconductive property 2.5 × 10–5 70 K. Optical also supports is...
Abstract From the viewpoints of large capacity, long‐term guarantee, and low cost, interest in magnetic recording tapes has undergone a revival as an archive storage media for big data. Herein, we prepared new series metal‐substituted ϵ‐Fe 2 O 3 , ϵ‐Ga III 0.31 Ti IV 0.05 Co II Fe 1.59 nanoparticles with average size 18 nm. Ga, Ti, cations tune properties to specifications demanded tape. The coercive field was tuned 2.7 kOe by introduction single‐ion anisotropy on ( S =3/2) along c‐axis....
Abstract Ferrite magnets have a long history. They are used in motors, magnetic fluids, drug delivery systems, etc. Herein we report mesoscopic ferrite bar magnet based on rod-shaped ε-Fe 2 O 3 with large coercive field (>25 kOe). The –based is single crystal domain along the longitudinal direction. A wide frequency range spectroscopic study shows that crystallographic -axis of , which corresponds to direction magnet, plays an important role linear and non-linear magneto-optical...
A zero thermal expansion (ZTE) material based on plate-shaped rubidium manganese hexacyanoferrate, Rb0.97Mn[Fe(CN)6]0.99·0.3H2O, is prepared using a polyethylene glycol monolaurate (PEGM) surfactant matrix. The microcrystals show charge transfer induced phase transition between the cubic MnII–NC–FeIII and tetragonal MnIII–NC–FeII phases. exhibits small negative (NTE) along aLT cLT axes with coefficient of α(aLT) = −1.40 ± 0.12 × 10–6 K–1 α(cLT) −0.17 0.13 over wide temperature range 15 K –...
We report a unique synthetic route toward the multistep spin crossover (SCO) effect induced by utilizing partial ligand transformation during crystallization process, which leads to incorporation of three different FeII complexes into single coordination framework. The 3-acetoxypyridine (3-OAcpy) molecules were introduced self-assembled FeII-[MIV(CN)8]4- (M = Mo, Nb) system in aqueous solution results hydrolysis 3-hydroxypyridine (3-OHpy). It gives two novel isostructural three-dimensional...
Extremely low-frequency optical phonon mode in Rb-intercalated two-dimensional cyanide-bridged Co–W bimetal assembly and its temperature- photo-induced switching effect.
Abstract We study by femtosecond optical pump‐probe spectroscopy the photoinduced charge transfer (CT) in RbMnFe Prussian blue analogue. Previous studies evidenced local nature of Mn III Fe II → process, occurring within less than 1 ps. Here we show experimentally that two photoswitching pathways exist, depending on excitation pump wavelength, which is confirmed band structure calculations. Photoexcitation α spins corresponds to Mn(d‐d) band, drives reverse Jahn–Teller distortion through...
Incorporating chiral organic ligands into cyanido-bridged Fe<sup>II</sup>–Nb<sup>IV</sup>assemblies synthesized spin-crossover complexes, which exhibit the temperature-dependent second harmonic light intensity change due to spin crossover.