0000000001316658

AUTHOR

Joaquim Marçalo

showing 4 related works from this author

A Mononuclear Uranium(IV) Single-Molecule Magnet with an Azobenzene Radical Ligand

2015

A tetravalent uranium compound with a radical azobenzene ligand, namely, [{(SiMe2NPh)3‐tacn}UIV(η2‐N2Ph2.)] (2), was obtained by one‐electron reduction of azobenzene by the trivalent uranium compound [UIII{(SiMe2NPh)3‐tacn}] (1). Compound 2 was characterized by single‐crystal X‐ray diffraction and 1H NMR, IR, and UV/Vis/NIR spectroscopy. The magnetic properties of 2 and precursor 1 were studied by static magnetization and ac susceptibility measurements, which for the former revealed single‐molecule magnet behaviour for the first time in a mononuclear UIV compound, whereas trivalent uranium compound 1 does not exhibit slow relaxation of the magnetization at low temperatures. A first approxim…

DiffractionUNESCO::QUÍMICARadicalOrganic Chemistrychemistry.chemical_elementGeneral ChemistryUranium7. Clean energy:QUÍMICA [UNESCO]CatalysisCrystallographychemistry.chemical_compoundMagnetizationchemistryAzobenzeneMagnetOrganic chemistrySingle-molecule magnetElectrostatic model
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A magnetic study of a layered lanthanide hydroxide family: Ln8(OH)20Cl4·nH2O (Ln = Tb, Ho, Er)

2018

Three layered lanthanide hydroxides (LLHs), with the general formula Ln8(OH)20Cl4·nH2O (Ln = Tb (1), Ho (2), Er (3)), were prepared and magnetically characterized. These compounds were further diluted within a yttrium diamagnetic matrix, LYH:xLn, LYH:0.044Tb (1’), LYH:0.045Ho (2’), and LYH:0.065Er (3’), being the study complemented with theoretical calculations in order to understand the electronic configuration and the contributions to the slow relaxation behavior. In the pure compounds dominant 3D ferromagnetic interactions are observed, with a small magnetization hysteresis at 1.8 K for 1, while the magnetically diluted solid solutions display slow relaxation of the magnetization at low …

LanthanideMaterials scienceRelaxation (NMR)chemistry.chemical_element02 engineering and technologyYttrium010402 general chemistry021001 nanoscience & nanotechnology01 natural sciences0104 chemical sciencesInorganic Chemistrychemistry.chemical_compoundMagnetizationchemistryFerromagnetismDiamagnetismHydroxidePhysical chemistry0210 nano-technologySolid solutionDalton Transactions
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Magnetic properties of the layered lanthanide hydroxide series Y(x)Dy(8-x)(OH)20Cl4·6H2O: from single ion magnets to 2D and 3D interaction effects.

2015

The magnetic properties of layered dysprosium hydroxides, both diluted in the diamagnetic yttrium analogous matrix (LYH:0.04Dy), and intercalated with 2,6-naphthalene dicarboxylate anions (LDyH-2,6-NDC), were studied and compared with the recently reported undiluted compound (LDyH = Dy8(OH)20Cl4·6H2O). The Y diluted compound reveals a single-molecule magnet (SMM) behavior of single Dy ions, with two distinct slow relaxation processes of the magnetization at low temperatures associated with the two main types of Dy sites, 8- and 9-fold coordinated. Only one relaxation process is observed in both undiluted LDyH and intercalated compounds as a consequence of dominant ferromagnetic Dy-Dy intera…

LanthanideRelaxation (NMR)Inorganic chemistrychemistry.chemical_elementYttriumInorganic ChemistryMagnetizationCrystallographyFerromagnetismchemistryCrystal field theoryDysprosiumDiamagnetismPhysical and Theoretical ChemistryInorganic chemistry
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CCDC 1054616: Experimental Crystal Structure Determination

2015

Related Article: Maria A. Antunes, Joana T. Coutinho, Isabel C. Santos, Joaquim Marçalo, Manuel Almeida, José J. Baldoví, Laura C. J. Pereira, Alejandro Gaita-Ariño, Eugenio Coronado|2015|Chem.-Eur.J.|21|17817|doi:10.1002/chem.201503133

Space GroupCrystallographyCrystal SystemCrystal StructureCell ParametersExperimental 3D Coordinates(diphenyldiazene)-((147-triazonane-147-triyl)tris(11-dimethyl-N-phenylsilanaminato))-uranium
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