Search results for "Magnetic Susceptibility"
showing 10 items of 516 documents
X-Ray structure of [ReCl4(μ-ox)Cu(pyim)2]: a new heterobimetallic ReIVCuIIferrimagnetic chain
2008
A new heterobimetallic Re(IV)Cu(II) compound has been prepared and its crystal structure determined by single-crystal X-ray diffraction; magnetic susceptibility measurements show that this compound behaves as a ferrimagnetic chain with significant antiferromagnetic interactions between Re(IV) and Cu(II) metal ions.
Synthesis, Structure, and Properties of BaVO2(AsO4): a New Vanadium Arsenate Containing the V2O42+ Core
1997
The new vanadium arsenate BaAsVO6 has been synthesized hydrothermally and structurally characterized by single-crystal X-ray diffraction, IR spectroscopy, and magnetic susceptibility measurements. It crystallizes in the monoclinic system, space group P21/c with unit cell parameters a = 5.645(1) A, b = 10.243(1) A, c = 8.945(1) A, β = 90.60(1)°, and Z = 2. The layered structure is built up from V2O42+ units and AsO43- anions, the AsO43- ligands being coordinated to two (V2O4)2+ units in both, terminal and bridging μ2-AsO43- fashion. The [VO2(AsO4)]2- layers are separated by Ba2+ cations. The V2O42+ unit has no precedence in oxo-vanadium chemistry.
Crystal structure, magnetic properties and esr studies of (4-apyH)4[CuIIBr4] [CuIBr2]2: a novel Cu(II)⧹Cu(I) system containing bromocuprate(I) chains…
1998
Abstract The synthesis, crystal structure, ESR spectra and magnetic properties are reported for the Cu(II)⧹Cu(I) compound (4-apyH)4[Cu3Br8] (4-apyH = C5H7N2 = 4-aminopyridinium). Single-crystals of the compound were grown by slow diffusion of n-hexane on an ethanolic solution of (4-apyH)2[CuBr4] · H2O. The crystal structure is made up of organic cations, isolated [CuIIBr4]2− anions and infinite [CuIBr2]nn− chains composed of edge-sharing CuIBr4 tetrahedra. N–H · · · Br hydrogen bond interactions between organic counter cations and inorganic anionic units are present and contribute to the cohesiveness of the crystal packing. Magnetic susceptibility measurements showed a good isolation of Cu(…
Copper(II) Complexes with Derivatives of Barbiturate
1984
Abstract NaCuL2(OH).1,5H2O, KCuP2(OH).1H2O, Na2CuL4 and K2CuP4-8H2O (HL=Phenobarbitone and HP=Methyl Phenobarbitone) were prepared and characterized by elemental analysis, IR and electronic spectral data and magnetic susceptibility measurements. The ESR spectra show and octahedral environment for the Cu(II) ion.
Further synthetic investigation of the general lanthanoid(iii) [Ln(iii)]/copper(ii)/pyridine-2,6-dimethanol/carboxylate reaction system: {CuII5LnIII4…
2021
In addition to previously studied {CuII3Gd6}, {CuII8Gd4}, {CuII15Ln7} and {CuII4Ln8} coordination clusters (Ln = trivalent lanthanide) containing pdm2− or Hpdm− ligands (H2pdm = pyridine-2,6-dimethanol) and ancillary carboxylate groups (RCO2−), the present work reports the synthesis and study of three new members of a fifth family of such complexes. Compounds [Cu5Ln4O2(OMe)4(NO3)4(O2CCH2But)2(pdm)4(MeOH)2] (Ln = Dy, 1; Ln = Tb, 2; Ln = Ho, 3) were prepared from the reaction of Ln(NO3)3·xH2O (x = 5, 6), CuX2·yH2O (X = ClO4, Cl, NO3; y = 6, 2 and 3, respectively), H2pdm, ButCH2CO2H and Et3N (2 : 2.5 : 2 : 1 : 9) in MeCN/MeOH. Rather surprisingly, the copper(II)/yttrium(III) analogue has a sli…
A rare isostructural series of 3d–4f cyanido-bridged heterometallic squares obtained by assembling [FeIII{HB(pz)3}(CN)3]− and LnIII ions: synthesis, …
2021
A new series of cyanido-bridged {FeIIILnIII}2 neutral molecular squares of general formula [Fe{HB(pz)3}(CN)(μ-CN)2Ln(NO3)2(pyim)(Ph3PO)]2·2CH3CN [Ln = Ce (1), Pr (2), Nd (3), Gd (4), Tb (5), Dy (6) and Er (7); {HB(pz)3}− = hydrotris(pyrazolyl)borate, pyim = 2-(1H-imidazol-2-yl)pyridine and Ph3PO = triphenylphosphine oxide] were obtained by reacting the low-spin [Fe{HB(pz)3}(CN)3]− species with the preformed [LnIII(pyim)(NO3)2(pyim)(Ph3PO)]+ complex anions (generated in situ by mixing the nitrate salt of each Ln(III) ion with pyim and Ph3PO molecules). Single-crystal X-ray diffraction studies show that 1–7 are isostructural compounds that crystallize in the triclinic P space group. Their cry…
The crystal structure and magnetic properties of 3-pyridinecarboxylate-bridged Re(ii)M(ii) complexes (M = Cu, Ni, Co and Mn)
2015
The novel Re(II) complex NBu4[Re(NO)Br4(Hnic)] (1) and the heterodinuclear compounds [Re(NO)Br4(μ-nic)Ni(dmphen)2]·½CH3CN (2), [Re(NO)Br4(μ-nic)Co(dmphen)2]·½MeOH (3), [Re(NO)Br4(μ-nic)Mn(dmphen)(H2O)2]·dmphen (4), [Re(NO)Br4(μ-nic)Cu(bipy)2] (5) [Re(NO)Br4(μ-nic)Cu(dmphen)2] (5') (NBu4(+) = tetra-n-butylammonium cation, Hnic = 3-pyridinecarboxylic acid, dmphen = 2,9-dimethyl-1,10-phenanthroline, bipy = 2,2'-bipyridine) have been prepared and the structures of 1-5 determined using single crystal X-ray diffraction. The structure of 1 consists of [Re(NO)Br4(Hnic)](-) anions and NBu4(+) cations. Each Re(II) is six-coordinate with four bromide ligands, a linear nitrosyl group and a nitrogen ato…
The Effect of Pressure on the Cooperative Spin Transition in the 2D Coordination Polymer {Fe(phpy) 2 [Ni(CN) 4 ]}
2013
The effect of pressure on the spin-transition properties of the 2D coordination polymer {Fe(phpy)2[Ni(CN)4]} is reported. The study has been carried out by means of variable-temperature (10–310 K) magnetic susceptibility measurements at applied pressures of 105 Pa to 1.0 GPa and spectroscopic studies in the visible region at room temperature (105 Pa–3.0 GPa). As the pressure is increased, the characteristic temperature of the spin transition is displaced to higher temperatures and the thermal hysteresis loop disappears. A cooperative first-order spin transition characterized by a piezo-hysteresis loop about 0.3 GPa wide was observed at 293 K.
Molecular anisotropy analysis of single-ion magnets using an effective electrostatic model.
2014
Simple electrostatic models have been shown to successfully rationalize the magnetic properties of mononuclear single molecule magnets based on f-elements and even to predict the direction of the magnetic anisotropy axis in these nanomagnets. In this Article, we go a step forward by showing that these models, conveniently modified to account for the covalency effects, are able to predict not only the easy axis direction but also the three components of the magnetic anisotropy. Thus, by using a lone pair effective charge (LPEC) model we can fully reproduce the angular dependence of the magnetic susceptibility in single crystals of pentamethylcyclopentadienyl-Er-cyclooctatetraene single-ion m…
Structural characterization and magnetic property studies of a mixed-valence {CoIIICoII4} complex with a μ4-oxo tetrahedral {CoII4} motif
2020
We have synthesized and structurally characterized a new mixed valence pentanuclear Co complex, bearing a rare μ4-O-tetrahedral CoII4 unit, by employing a pyridine-like Schiff base ligand. We have performed DC magnetic susceptibility and magnetization measurements over polycrystalline samples and chemical quantum computations in order to understand the exchange interaction pattern within Co(II) sites and ground state magnetic anisotropy. This new complex shows an overall antiferromagnetic exchange interaction whose strength strongly depends on the local symmetry of Co(II) sites. Also, local ion magnetic anisotropy reveals a strongly axial behaviour with the lowest Kramers doublet (KD) at ea…