Search results for "Magnetism"

showing 10 items of 1934 documents

Synthesis, characterization and magnetic properties of mixed-valence iron complexes with 2-pyridyl oximes

2018

Two new mixed-valence iron complexes with 2-pyridyl oximes, [Fe(mpko)3Fe(H2O)2(NO3)](NO3)·2H2O (1) (mpko− = methyl(2-pyridyl)ketone oximate) and [{Fe(dpko)3}2Fe](ClO4)·4H2O (2) (dpko− = bis(2-pyridyl)ketone oximate), have been prepared by reaction of FeIII with mpkoH in methanol (1) and FeII with dpkoH in methanol/water (2). Dinuclear FeII(low-spin)FeIII(high-spin) and trinuclear FeII(low-spin)FeIII(high-spin)FeII(low-spin) cations are present in the crystal structure of 1 and 2, respectively. Intermolecular hydrogen bonds in 1 lead to weak antiferromagnetic interactions between pairs of neighboring FeIII centers, which allows observation of single-ion zero-field splitting effects.

chemistry.chemical_classificationValence (chemistry)Ketone010405 organic chemistryChemistryHydrogen bondIntermolecular forceCrystal structure010402 general chemistry01 natural sciences0104 chemical sciencesMethyl 2-pyridyl ketone oximechemistry.chemical_compoundCrystallographyMaterials ChemistryAntiferromagnetismMethanolPhysical and Theoretical Chemistry
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Molecular magnetism, quo vadis? A historical perspective from a coordination chemist viewpoint☆

2017

Abstract Molecular magnetism has travelled a long way from the pioneering studies on electron exchange and double exchange or spin crossover and valence tautomerism in small oligonuclear complexes, from mono- to di- and tetranuclear species, to the current investigations about magnetic anisotropy and spin dynamics or quantum coherence of simple mono- or large polynuclear complexes, behaving as switchable bistable molecular nanomagnets for potential applications in information data storage and processing. In this review, we focus on the origin and development of the research in the field of molecular magnetism from a coordination chemistry viewpoint, which dates back to the establishment of …

chemistry.chemical_classificationValence (chemistry)Spintronics010405 organic chemistryMagnetismNanotechnology010402 general chemistry01 natural sciences0104 chemical sciencesCoordination complexInorganic ChemistrychemistrySpin crossoverMagnetochemistryMaterials ChemistryPhysical and Theoretical ChemistryQuantumQuantum computerCoordination Chemistry Reviews
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Spin Polarization and Ferromagnetism in Two-Dimensional Sheetlike Cobalt(II) Polymers: [Co(L)2(NCS)2] (L=Pyrimidine or Pyrazine)

1998

chemistry.chemical_classificationchemistry.chemical_compoundFerromagnetismPyrimidinechemistrySpin polarizationPyrazinechemistry.chemical_elementGeneral ChemistryPolymerPhotochemistryCobaltCatalysisAngewandte Chemie International Edition
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ChemInform Abstract: Multifunctionality in Hybrid Magnetic Materials Based on Bimetallic Oxalate Complexes

2011

This tutorial review illustrates the design of multifunctional oxalate-based magnetic materials through the combination of the intrinsic magnetism of the metal–organic framework and the additional properties introduced by several organic/inorganic functional cations.

chemistry.chemical_compoundChemical engineeringChemistryMagnetismGeneral Medicineequipment and supplieshuman activitiesBimetallic stripOxalateChemInform
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Cover Picture: Insertion of a Single-Molecule Magnet inside a Ferromagnetic Lattice Based on a 3D Bimetallic Oxalate Network: Towards Molecular Analo…

2014

chemistry.chemical_compoundCrystallographyFerromagnetismChemistryMagnetLattice (order)Organic ChemistryX-ray crystallographySingle-molecule magnetGeneral ChemistryBimetallic stripCatalysisOxalateChemistry - A European Journal
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Titelbild: Cyanide-Bridged Iron(III)–Cobalt(II) Double Zigzag Ferromagnetic Chains: Two New Molecular Magnetic Nanowires (Angew. Chem. 13/2003)

2003

chemistry.chemical_compoundCrystallographyMaterials scienceZigzagchemistryFerromagnetismCyanidechemistry.chemical_elementNanotechnologyGeneral MedicineMagnetic nanowiresCobaltAngewandte Chemie
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Syntheses, crystal structures and magnetic properties of polynuclear 1,4,5,8,9,12-hexaazatriphenylene (hat)-bridged copper(II) complexes

2001

Three polynuclear compounds containing copper(II) and 1,4,5,8,9,12-hexaazatriphenylene (hat) as the basic building blocks have been prepared, [Cu4(hat)2Cl8]n·6nH2O 1, [Cu(hat)(H2O)2]n[NO3]2n2, and [Cu2(hat)(H2O)6]n[SO4]2n·2nH2O 3, their crystal structures determined and variable-temperature magnetic susceptibility data measured. The basic building block in 1 is the dinuclear [Cu2(hat)Cl4] entity, two such units being connected to tetranuclear units through relatively strong axial Cu–Cl bonds (out-of-plane di-μ-chloro bridges). Weaker axial Cu⋯Cl interactions link the units into a sheet structure. In 2 and 3 hat-bridged copper(II) chains extending along glide planes are present. hat serves a…

chemistry.chemical_compoundCrystallographyPyrazinechemistryOctahedronIntramolecular forceAntiferromagnetismchemistry.chemical_elementGeneral ChemistryCrystal structureMagnetic susceptibilityCopperSquare pyramidal molecular geometryJournal of the Chemical Society, Dalton Transactions
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A Covalently Cross-linked Polyetheretherketone Proton Exchange Membrane for DMFC

2009

The proton exchange membrane was prepared by covalent cross-linking sulfonated-sulfinated polyetheretherketone. The cross-linked membrane showed high proton conductivity (0.04 S/cm) with suitable water uptake, low methanol permeability (2.21 × 10-7 cm2/s) and good electrochemical stability. The results suggested that cross-linked polyetheretherketone membrane is particularly promising to be used as proton exchange membrane for the direct methanol fuel cell application.

chemistry.chemical_compoundDirect methanol fuel cellMembranechemistryChemical engineeringCovalent bondPermeability (electromagnetism)Polymer chemistryProton exchange membrane fuel cellMethanolConductivityElectrochemistryECS Meeting Abstracts
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Magnetization Relaxation in a Three‐Dimensional Ligated Cobalt Phosphonate Containing Ferrimagnetic Chains

2010

chemistry.chemical_compoundMagnetizationCrystallographychemistryFerrimagnetismOrganic ChemistryInorganic chemistryRelaxation (physics)chemistry.chemical_elementGeneral ChemistryPhosphonateCobaltCatalysisChemistry – A European Journal
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Magneto-Transport Results in Alq3 Based OSVs

2015

The achievement of good magnetoresistance signal at room temperature is an important requirement for the possible future development of organic devices for applications. However, until now only few works reported room temperature MR effect in organic spin valves (OSVs). In this regard, this chapter is dedicated to the investigation of Alq3-based OSVs where Alq3 molecule was chosen since it is a standard material in the field. A systematic study on Co/Alq3/Co OSVs will be presented showing room temperature MR results. Moreover, inelastic electron tunneling spectroscopy (IETS) technique will be used to prove spin injection into the organic layer. Finally, an insulating oxide barrier (Al2O3 or…

chemistry.chemical_compoundMaterials scienceFerromagnetismSpin polarizationMagnetoresistancechemistryCondensed matter physicsInelastic electron tunneling spectroscopySpin valveOxideMagnetoSpin-½
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