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Single-molecule Magnets (single-molecule + magnet)

Distribution by Scientific Domains
Chemistry84%

Selected Abstracts

A Liquid-Crystalline Single-Molecule Magnet with Variable Magnetic Properties,

ANGEWANDTE CHEMIE, Issue 9 2010
Mathieu Gonidec
Ein Terbium-Phthalocyanin -Doppeldeckerkomplex wurde hergestellt und charakterisiert. Die Mesomorphie des flüssigkristallinen Komplexes wurde genutzt, um seine magnetischen Eigenschaften durch einfache thermische Behandlung reversibel zu modifizieren. [source]

A Polynuclear Lanthanide Single-Molecule Magnet with a Record Anisotropic Barrier,

ANGEWANDTE CHEMIE, Issue 50 2009
Po-Heng Lin
Magnetische Messungen an einem {Dy4}-Einzelmolekülmagneten (SMM) mit einem defekten Dicuban als Kern, der mithilfe von 1,2-Bis(2-hydroxy-3-methoxybenzyliden)hydrazon und 3-Methoxysalicylaldehydhydrazon als Chelatbildner synthetisiert wurde (siehe Struktur; gelb Dy, rot O, blau , grün Cl), bestätigen das SMM-Verhalten und zeigen Hystereseschleifen bei 7,K. Die Anisotropiebarriere von Ueff=170,K stellt den höchsten bislang erreichten Wert dar. [source]

Cobalt Antiferromagnetic Ring and Grid Single-Molecule Magnet

CHEMISTRY - AN ASIAN JOURNAL, Issue 11 2009
Takuya Shiga Dr.
Grid magnet: A Co8 ring and a Co9 grid complex are synthesized using a multidentate polypyridine-type ligand and are shown to exhibit all antiferromagnetic interactions between metal centers, with the grid complex displaying SMM properties as a result of alternating high spin/low spin metal centers in the outer 8-membered ring. [source]

Ferrocene-Substituted [Mn4] Dicubane Single-Molecule Magnets

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2009
Katie J. Heroux
Abstract Two new mixed-valent [Mn4] single-molecule magnets (SMMs) have been synthesized by using N -alkylated diethanolamine ligands and ferrocenecarboxylic acid. Both complexes exhibit weak ferromagnetic exchange and appreciable axial zero-field splitting as evidenced by DC magnetic susceptibility and field-dependent magnetization measurements. A significant frequency-dependent out-of-phase signal in the AC susceptibility is also observed for both complexes, a feature that is characteristic of SMMs. The ground-state spin of each complex was determined from the DC data and extrapolation of the low-frequency AC data, giving a value of S = 8. This result is consistent with the previously reported and structurally similar S = 8 and S = 9 [Mn4] dicubane SMMs. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]

Calix[4]arene-Based Single-Molecule Magnets,

ANGEWANDTE CHEMIE, Issue 44 2009
Georgios Karotsis
Schützende Haut: Einzelmolekülmagnete (SMMs), die durch zwei Calix[4]arene geschützt sind, wurden synthetisiert (siehe Bild: Mn violett, O rot, N blau, C grau). Das Calixaren isoliert die SMMs, und durch Modifizieren seines oberen Randes können die Abstände zwischen den Schichten und damit die Festkörperpackung verändert werden. [source]

ChemInform Abstract: Switching Slow Relaxation in a MnIII3MnIV Cluster: An Example of Grafting Single-Molecule Magnets onto Polyoxometalates.

CHEMINFORM, Issue 28 2010
Xikui Fang
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

ChemInform Abstract: Magnetic Bistability of Individual Single-Molecule Magnets Grafted on Single-Wall Carbon Nanotubes.

CHEMINFORM, Issue 36 2009
Gaelle Charron
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

Ferrocene-Substituted [Mn4] Dicubane Single-Molecule Magnets

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2009
Katie J. Heroux
Abstract Two new mixed-valent [Mn4] single-molecule magnets (SMMs) have been synthesized by using N -alkylated diethanolamine ligands and ferrocenecarboxylic acid. Both complexes exhibit weak ferromagnetic exchange and appreciable axial zero-field splitting as evidenced by DC magnetic susceptibility and field-dependent magnetization measurements. A significant frequency-dependent out-of-phase signal in the AC susceptibility is also observed for both complexes, a feature that is characteristic of SMMs. The ground-state spin of each complex was determined from the DC data and extrapolation of the low-frequency AC data, giving a value of S = 8. This result is consistent with the previously reported and structurally similar S = 8 and S = 9 [Mn4] dicubane SMMs. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]

Magnetic Materials: X-Ray Magnetic Circular Dichroism Picks out Single-Molecule Magnets Suitable for Nanodevices (Adv. Mater.

ADVANCED MATERIALS, Issue 2 2009
2/2009)
The surface sensitivity of X-ray magnetic circular dichroism in extreme conditions has been exploited to investigate the first layers of bulk single-molecule magnets (SMMs), as reported by Roberta Sessoli and co-workers on p. 167. Striking differences have emerged between two classes of SMM having different structural constraints, thus highlighting the importance of molecular design in the realization of molecular spintronic devices. [source]

X-Ray Magnetic Circular Dichroism Picks out Single-Molecule Magnets Suitable for Nanodevices

ADVANCED MATERIALS, Issue 2 2009
Matteo Mannini
The surface sensitivity of X-ray Magnetic Circular Dichroism in extreme conditions is exploited to investigate the first layers of bulk single-molecule magnets (SMM). Striking differences emerge between two classes of SMM with different structural constraints, thus highlighting the importance of molecular design in the realization of molecular spintronic devices [source]

How to Build Molecules with Large Magnetic Anisotropy

CHEMISTRY - A EUROPEAN JOURNAL, Issue 16 2009
Jordi Cirera Dr.
Abstract Predicting single-molecule magnets? Magnetic anisotropy, a property that plays a key role in single-molecule magnets (SMMs), has been analyzed by using theoretical methods. Mononuclear complexes and the dependence of the magnetic anisotropy on their geometrical and electronic structure, as well as how such mononuclear complexes must be combined as building blocks to obtain polynuclear complexes with large anisotropy (see figure) are considered. The magnetic anisotropy of mononuclear transition-metal complexes has been studied by means of electronic structure calculations based on density functional theory. The variation of the zero-field splitting (ZFS) parameters has been analyzed for the following characteristic distortions: a tetragonal Jahn,Teller distortion, the Bailar twist, the Berry pseudorotation, and the planarization of tetrahedral complexes. Finally, the coupling of mononuclear building blocks in polynuclear complexes to obtain a large negative magnetic anisotropy necessary to improve their single-molecule-magnet (SMM) behavior has been studied. [source]

Electronic and Magnetic Properties of Bimetallic Ytterbocene Complexes: The Impact of Bridging Ligand Geometry

CHEMISTRY - A EUROPEAN JOURNAL, Issue 2 2008
Christin
Abstract Bimetallic ytterbocene complexes with bridging N-heterocylic ligands have been studied extensively in recent years due to their potential applications ranging from molecular wires to single-molecule magnets. Herein, we review our recent results for a series of ytterbocene polypyridyl bimetallic complexes to highlight the versatility and tunability of these systems based on simple changes in bridging ligand geometry. Our work has involved structural, electrochemical, optical, and magnetic measurements with the goal of better understanding the electronic and magnetic communication between the two ytterbium metal centers in this new class of bimetallics. [source]