Search results for "Ferrimagnetism"

[Criii(L)(CN)4]−: a new building block in designing cyanide-bridged 4,2-ribbon-like chains {[Criii(L)(CN)4]2Mn(H2O)2}·nH2O [L = 2-aminomethylpyridine…

2005

The preparation, X-ray crystallography and magnetic study of compounds PPh4[Cr(ampy)(CN)4]·H2O (1), PPh4[Cr(phen)(CN)4]·H2O·CH3OH (2), {[Cr(ampy)(CN)4]2Mn(H2O)2}·6H2O (3) and {[Cr(phen)(CN)4]2Mn(H2O)2}·4H2O (4), with PPh4+ = tetraphenylphosphonium cation, ampy = 2-aminomethylpyridine and phen = 1,10-phenanthroline, are reported here. 1 and 2 are mononuclear complexes whereas 3 and 4 are 4,2-ribbon-like bimetallic chains. The magnetic properties of 1–4 were investigated in the temperature range 1.9–300 K. A quasi Curie law behaviour for a magnetically isolated spin quartet is observed for 1 and 2. Compounds 3 and 4 are ferrimagnetic CrIII2MnII chains, which exhibit a metamagnetic behaviour, …

The dynamics of magnetic ordering in a natural hemo-ilmenite solid solution

2007

Geophysical Journal International, 169 (3)

Growth of thin films of single-chain magnets on functionalized silicon surfaces

2018

A one-pot strategy for the direct growth of continuous and regular thin films of a neutral oxamato-bridged heterobimetallic chain, synthesized from Co2+ nitrate and the tetramethylammonium salt of the anionic copper(II) complex (Me4N)2[Cu(2,6-Et2pa)2]·6H2O (1) (2,6-Etpa = N-2,6-diethylphenyloxamate) over Si(111) surfaces functionalized with carboxylic acid terminating groups has been developed. Variation of the growth conditions can provide important differences in the morphology of the obtained films when working in H2O at 20 °C. An anisotropic growth of 1-D fibers is observed under stoichiometric conditions (Co2+/1 = 1:1), while an isotropic growth of 3-D particles occurs for an excess of…

Direct observation of coherent magnons with suboptical wavelengths in a single crystalline ferrimagnetic insulator

2019

In the field of magnetism, spin waves are a subject of great interest for fundamental and application-oriented research. Time-resolved scanning transmission x-ray microscopy, a technique that allows for direct spin-wave imaging below the optical resolution limit, is usually limited to thin layers deposited on x-ray transparent membranes. Here, the authors report on a preparation routine that makes single-crystalline materials accessible to this powerful technique. The latter is subsequently implemented on the ferrimagnetic insulator yttrium iron garnet, where spin waves down to 100-nm wavelength are observed.

Synthesis of the first heterometalic star-shaped oxido-bridged MnCu3 complex and its conversion into trinuclear species modulated by pseudohalides (N…

2011

A tetra-nuclear, star-shaped hetero-metallic copper(II)-manganese(II) complex, [{CuL(H(2)O)}(2)(CuL)Mn](ClO(4))(2) (1) has been synthesized by reacting the "complex as ligand" [CuL] with Mn(ClO(4))(2) where H(2)L is the tetradentate di-Schiff base derived from 1,3-propanediamine and 2-hydroxyacetophenone. Upon treatment with the polyatomic anions azide, cyanate, or thiocyanate in methanol medium, complex 1 transforms into the corresponding trinuclear species [(CuL)(2)Mn(N(3))(2)] (2), [(CuL)(2)Mn(NCO)(2)] (3) and [(CuL)(2)Mn(NCS)(2)] (4). All four complexes have been structurally and magnetically characterized. In complex 1 the central Mn(II) ion is encapsulated by three terminal [CuL] unit…

Spin control in oxamato-based manganese(II)-copper(II) coordination polymers with brick-wall layer architectures.

2011

Two new heterobimetallic manganese(II)-copper(II) coordination polymers of formulas [Mn(2)Cu(2)(Me(3)mpba)(2)(H(2)O)(6)]·8H(2)O (1) and [Mn(2)Cu(2)(Me(4)ppba)(2)(H(2)O)(6)]·8H(2)O (2) [Me(3)mpba = 2,4,6-trimethyl-N,N'-1,3-phenylenebis(oxamate) and Me(4)ppba = 2,3,5,6-tetramethyl-N,N'-1,4-phenylenebis(oxamate)] have been synthesized following a molecular-programmed self-assembly method from the corresponding dicopper(II) complexes acting as metalloligands toward Mn(II) ions. 1 and 2 consist of neutral Mn(II)(2)Cu(II)(2) layers with a brick-wall structure made up of oxamato-bridged Mn(II)Cu(II) chains connected through double meta- (1) and para-substituted (2) permethylated phenylene spacers.…

A Three-Dimensional Homometallic Molecular Ferrimagnet

2002

A neutral 2D oxalate-based soluble magnet assembled by hydrogen bonding interactions

2008

Abstract Herein we describe the synthesis, structure and magnetic properties of a novel oxalate-based layered magnetic system: {[Mn(OH2)2(S)2][Mn(S)(OH2)]2[Cr(ox)3]2(18-crown-6)}∞ (S = CH3OH; ox = C 2 O 4 2 - ; 18-crown-6 = C12H24O6) (1). In this case, no cationic templating agent is required to promote the assembling of low-dimensional oxalate-bridged metallic complexes in solution. Instead, strong enough hydrogen bonding interactions are responsible for their packing in the solid state. This magnet is soluble and presents two different types of oxalate bridges: the common bis(bidentate) and the unusual bidentate–monodentate. This structural feature has drastic consequences on the magnetis…

Graphene related magnetic materials: micromechanical exfoliation of 2D layered magnets based on bimetallic anilate complexes with inserted [FeIII(aca…

2015

The syntheses, structures and magnetic properties of the coordination compounds of formula [FeIII(acac2-trien)][MnIICrIII(Cl2 An)3]·(CH3CN)2 (1), [FeIII(acac2-trien)][MnIICrIII(Br2An)3]·(CH3CN)2 (2) and [GaIII(acac2-trien)][MnIICrIII(Br2An)3]·(CH3CN)2 (3) are reported. They exhibit a 2D anionic network formed by Mn(II) and Cr(III) ions linked through anilate ligands, while the [FeIII(acac2-trien)]+ or [GaIII(acac2-trien)]+ charge-compensating cations are placed inside the hexagonal channels of the 2D network, instead of being inserted in the interlamellar spacing. Thus, these crystals are formed by hybrid layers assembled through van der Waals interactions. The magnetic properties indicate …

Synthesis, crystal structures and magnetic properties of M(II)Cu(II) chains (M = Mn and Co) with sterically hindered alkyl-substituted phenyloxamate …

2011

A series of neutral oxamato-bridged heterobimetallic chains of general formula [MCu(L(x)2 (S)2] · p S · q H2O [p = 0-1, q = 0-2.5; L1 = N-2,6-dimethylphenyloxamate, S = DMF with M = Mn (1a) and Co (1b); L2 = N-2,6-diethylphenyloxamate, S = DMF with M = Mn (2a) and Co (2b) or S = DMSO with M = Mn (2c) and Co (2 d); L3 = N-2,6-diisopropylphenyloxamate, S = DMF with M = Mn (3a) and Co (3b) or S = DMSO with M = Mn (3c) and Co (3d)] were prepared by treating the corresponding anionic oxamatocopper(II) complexes [Cu(L(x))(2)]2- (x = 1-3) with M(2+) cations (M = Mn and Co) in DMF or DMSO as the solvent. The single-crystal X-ray structures of 2a and 3a reveal the occurrence of well-isolated, zigzag…