A5074840377- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Magnetism in coordination complexes
- Crystallography and molecular interactions
- Electron Spin Resonance Studies
- Lanthanide and Transition Metal Complexes
- Organic and Molecular Conductors Research
- Metal complexes synthesis and properties
- Metal-Organic Frameworks: Synthesis and Applications
- Porphyrin and Phthalocyanine Chemistry
- Luminescence and Fluorescent Materials
- Polyoxometalates: Synthesis and Applications
- Molecular Sensors and Ion Detection
- Chemical Synthesis and Characterization
- Advanced Condensed Matter Physics
- Supramolecular Chemistry and Complexes
- Physics of Superconductivity and Magnetism
- Advanced NMR Techniques and Applications
- Nonlinear Dynamics and Pattern Formation
- Nitric Oxide and Endothelin Effects
- Inorganic Chemistry and Materials
- Nanocluster Synthesis and Applications
- Quantum and electron transport phenomena
- Chemical and Physical Studies
- Ionic liquids properties and applications
Hiroshima University
2014-2024
Novosibirsk State University
2004-2023
International Tomography Center
2010-2023
Suzugamine Women's College
2016
Siberian Branch of the Russian Academy of Sciences
2013-2015
Graduate School USA
2015
Institute of Chemical Kinetics and Combustion
2010
Weizmann Institute of Science
2008
ETH Zurich
2007
In the overwhelming majority of exchange-coupled clusters investigated in field molecular magnetism, exchange interaction is constant on temperature. "Breathing" crystals composition Cu(hfac)2LR undergo temperature-induced reversible structural rearrangements accompanied by significant changes effective magnetic moment. Using high-field (W-band) EPR, we provide a solid proof drastic temperature dependence J(T) these compounds that originates from inter-spin distances. Strong revealed EPR...
We succeeded in synthesizing of a whole family isostructural solvates the copper(II) hexafluoroacetylacetonate complex with pyrazolyl-substituted nitronyl nitroxide (L): Cu(hfac)2L·0.5Solv. The main feature inherent nature Cu(hfac)2L·0.5Solv single crystals is their incredible mechanical stability and ability to undergo reversible structural rearrangements temperature variation, accompanied by anomalies on μeff(T) dependence. Structural investigation complexes over wide range before after...
Polymer-chain complexes Cu(hfac)2LR represent an interesting type of molecular magnets exhibiting thermally induced and light-induced magnetic switching, in many respects similar to a spin crossover. In the majority these compounds polymer chain consists alternating one- three-spin units composed copper(II) ions nitronyl nitroxides. The principal one-dimensional structure has previously been assumed play key role observed anomalies. Using Q-band electron paramagnetic resonance (EPR)...
A new group of "breathing" crystals has been synthesized. These are aromatic solvates the copper(II) hexafluoroacetylacetonate complex with spin-labeled pyrazole Cu(hfac)(2)L·0.5Solv, where L is 2-(1-butyl-1H-pyrazol-4-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl and Solv benzene, toluene, ethylbenzene, propylbenzene, butylbenzene, styrene, o-xylene, m-xylene, p-xylene, 1,4-bis(trifluoromethyl)benzene, 1-methyl-4-ethylbenzene, 1-methyl-4-vinylbenzene, 1,4-diethylbenzene,...
Thermally induced spin transitions in a family of heterospin polymer chain complexes Cu2+ hexafluoroacetylacetonate with two pyrazole-substituted nitronyl nitroxides are studied using electron paramagnetic resonance (EPR) spectroscopy. The structural rearrangements at low temperatures induce exchange-coupled triads nitroxide-copper(II)-nitroxide. values exchange interactions systems typically on the order tens to hundreds inverse centimeters. large magnitude interaction determines specific...
Molecular magnets Cu(hfac)(2)L(R) represent a new type of photoswitchable materials based on exchange-coupled clusters copper(II) with stable nitroxide radicals. It was found recently that the photoinduced spin state these compounds is metastable time scale hours at cryogenic temperatures, similar to light-induced excited trapping phenomenon well-known for many spin-crossover compounds. Our previous studies have shown electron paramagnetic resonance (EPR) in continuous wave (CW) mode allows...
Most photoswitchable molecular magnets exhibit thermally induced switching, as is typical of spin crossover (SCO), valence tautomerism and SCO-like phenomena. We report a rare case copper-nitroxide based magnet Cu(hfac)2Li-Pr that does not quantitative behavior in the temperature range its chemical stability (2–350 K); however, it can be switched to metastable inaccessible state via visible/near-IR light at cryogenic temperatures. By means photogeneration, unique information on this...
The synthesis of artificial ion channels is one the core areas biomimetics and aimed at achieving control over channel functionality by careful design selection constituent components. However, optimization ionic conductivity in crystalline state challenging because crystal strain, polymorphism, potentially limited stability. In this study, pore size cylindrical was controlled with aim optimizing conductivity. We prepared two isomorphic salts, Li2([18]crown-6)3[Ni(dmit)2]2(H2O)4 (1)...
We report the first example of polymer-chain breathing crystals whose paramagnetic properties are suppressed by lowering temperature and/or increase pressure.
A series of 2-(1-R-pyrazol-4-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl radicals (NN-4PzR) was synthesized and structurally magnetochemically characterized. comprehensive comparative crystallochemical analysis quantum chemical calculations were carried out in new and...
Exchange-coupled spin triads nitroxide–copper(II)–nitroxide are the key building blocks of molecular magnets Cu(hfac)2LR. These compounds exhibit thermally induced structural rearrangements and transitions, where exchange interaction between spins copper(II) ion nitroxide radicals changes typically by 1 order magnitude. We have shown previously that electron paramagnetic resonance (EPR) spectroscopy is sensitive to observed magnetic anomalies provides information on both inter- intracluster...
Abstract In contrast to diradicals connected by alternant hydrocarbons, only a few studies on those nonalternant hydrocarbons have been reported. The syntheses, structures, and magnetic properties of azulene‐1,3‐diyl linked bis(nitronyl nitroxide) (NN 2 Az) bis(iminonitroxide) (IN their Cu(hfac) (hfac=hexafluoroacetylacetonate) complexes were investigated. NN Az was shown an intramolecular ferromagnetic interaction with J obs / k B =+10.0 K ( H =−2 S 1 ⋅S ) between (nitronyl spins, whereas...
Molecular magnets Cu(hfac)2LR (hfac = hexafluoroacetylacetonate) called "breathing crystals" exhibit thermally and light-induced magnetic anomalies very similar to iron(II) spin-crossover compounds. They are physically different systems, because the spin-state switching occurs in exchange-coupled nitroxide–copper(II)–nitroxide clusters, contrast classical spin crossover d4–d7 transition ions. Despite this difference, numerous similarities physical behavior of these two types compounds have...
The spin transition temperature of the Cu(<sc>ii</sc>)-nitroxide complex was found to shift by approximately 100 K toward higher temperatures when hydrostatic pressure increased ∼0.04 GPa.
Pronounced thermochromism of copper(<sc>ii</sc>)–nitroxide based molecular magnets is explained.
"Breathing crystals" based on copper(II) hexafluoroacetylacetonates and pyrazolyl-substituted nitronyl nitroxides comprise the exchange-coupled clusters within polymeric chains. Owing to an interplay of exchange interaction between nitroxide spins Jahn–Teller nature complex, breathing crystals demonstrate thermally light-induced magnetostructural transitions in many aspects similar classical spin crossover. Herewith, we report first application variable temperature (VT) far/mid Fourier...
A study of the single-crystal-to-single-crystal transformation induced by temperature variation for chain polymer Cu(II) complex with nitronyl nitroxide showed that an increase in hydrostatic pressure up to ∼0.07 GPa completely changes intracrystalline displacements molecules relative one another. This, turn, significantly affects interaction energy unpaired electrons paramagnetic centers and hence form dependence magnetic susceptibility χT. The cooling crystals under normal conditions...
We report the synthesis of a reduced Preyssler-type polyoxometalate (POM), using Ag-containing POM. Both parent and clusters were obtained in monocrystalline form, allowing structure determination by single-crystal X-ray diffraction. Furthermore, photoelectron spectroscopy, cyclic voltammetry, magnetic susceptibility measurements suggested that cluster exhibits valence −23 Ag present POM exists neutral state.
Artificial ion channels are of increasing interest because potential applications in biomimetics, for example, realizing selective permeability through the transport and/or exchange selected ions. However, crystalline state is rare, and to best our knowledge, such a process has not been successfully combined with changes physical properties material. Herein, by soaking single crystals Li2 ([18]crown-6)3 [Ni(dmit)2 ]2 (H2 O)4 (1) an aqueous solution containing K+ , we succeeded complete Li+...