Search results for "Magnetic Susceptibility"
showing 10 items of 516 documents
Magnetic properties of quasi-2D antiferromagnet {N(n-C5H11)4[MnIIFeIII(ox)3]}∞ below Néel temperature: revisited
2004
Abstract Magnetic measurements of {N(n-C 5 H 11 ) 4 [Mn II Fe III (ox) 3 ]} ∞ were carried out in the 5–300 K temperature range under different applied magnetic fields up to 50 kOe with zero-field-cooled (ZFC) and field-cooled (FC) modes. The FC and ZFC χ ( T ) plots exhibited a significantly large bifurcation below the transition temperature, which was traceable even at 50 kOe of applied magnetic field. The bifurcation temperature was found to be magnetic field dependent for the lower range of magnetic fields, which can be represented by a polynomial of magnetic field. The observed magnetic transition temperature of this compound was in good agreement with the earlier reported results. The…
Geostatistical 3-dimensional integration of measurements of soil magnetic susceptibility.
2010
In soil magnetometry, two types of measurements are usually performed. The first type is measurements performed on the soil surface, frequently using an MS2D sensor. The second type includes measurements of magnetic susceptibility carried out in the soil profile, usually to a depth of about 30 cm. Up to now, such measurement results were analyzed separately. However, it is possible and advantageous to integrate these two types of measurements. The goal of the study was to integrate measurements of magnetic susceptibility performed on the soil surface and in the soil profile. More specifically, the goal was to obtain 3-dimensional spatial distributions of magnetic susceptibility of the topso…
Isomorphous replacement of MII ions in MII–GdIII dimers (MII = CuII, MnII, NiII, CoII, ZnII): magnetic studies of the products
2011
Complexes [M(II)Gd(III){pyCO(OEt)pyC(OH)(OEt)py}₃](ClO₄)₂·EtOH [M(II) = Cu(II) (1), Mn(II) (2), Ni(II) (3), Co(II) (4) and Zn(II) (5)] crystallize in the monoclinic Cc space group and contain one hexacoordinate M(II) ion and one enneacoordinate Gd(III) ion, bridged by three {pyCO(OEt)pyC(OH)(OEt)py}⁻ ligands. Magnetic susceptibility measurements indicate a ferromagnetic interaction for 1 and antiferromagnetic interactions for 2-4. Using the Ĥ = -JŜ(Gd(III))Ŝ(M(II)) spin Hamiltonian formalism, fits to the magnetic susceptibility data yielded J values of +0.32 cm⁻¹ for 1, -1.7 cm⁻¹ for 2, and -0.22 cm⁻¹ for 3. In complex 4, the orbital contributions of Co(II) precluded the determination of th…
Synthesis and characterisation of a novel ferrimagnetic chain based on copper(II) and rhenium(IV)
2019
Abstract A novel one-dimensional copper(II)–rhenium(IV) coordination polymer of formula {[ReIVBr4(μ-ox)CuII(pyim)2]·MeCN}n (1) [ox = oxalate anion, pyim = 2-(2′-pyridyl)imidazole] has been prepared and characterised. Powder X-ray diffraction measurements on a sample of 1 support the purity of the bulk sample, whereas single-crystal X-ray diffraction shows that 1 crystallises in the orthorhombic system with space group Pbca. The crystal structure of 1 is made up of [CuII(pyim)2]2+ cations and [ReBr4(ox)]2− anions linked through bridging bromide and oxalate groups, which generate alternating CuII and ReIV chains. Variable-temperature magnetic susceptibility measurements performed on 1 reveal …
Halogen⋯halogen interactions in the self-assembly of one-dimensional 2,2′-bipyrimidine-based CuIIReIV systems
2018
Two one-dimensional CuIIReIV coordination polymers of the general formula {[ReIVCl4(μ-bpym)CuIIX2]·solvent}n [where bpym = 2,2′-bipyrimidine, X = Cl (1) and Br (2), and solvent = H2O (1) and CHCl3 (2)] have been prepared and characterised structurally and magnetically. Both compounds crystallise in the monoclinic system with space groups P21/c (1) and P21/n (2). Each CuII ion is bonded to two cis nitrogen atoms from the bpym ligand and to four halogen atoms. Two of these halogen atoms are placed in the equatorial plane and the other two are filling the axial positions of the CuII ion, thus generating a distorted octahedral environment for this metal ion in 1 and 2. In both compounds, the Re…
The influence of pseudohalide ligands on the SIM behaviour of four-coordinate benzylimidazole-containing cobalt(ii) complexes.
2018
Three, mononuclear complexes of the formula [Co(bmim)2(SCN)2] (1), [Co(bmim)2(NCO)2] (2) and [Co(bmim)2(N3)2] (3) [bmim = 1-benzyl-2-methylimidazole] were prepared and structurally analyzed by single-crystal X-ray crystallography. The cobalt(ii) ions in 1-3 are tetrahedrally coordinated with two bmim molecules and two pseudohalide anions. The angular distortion parameter δ was calculated and the SHAPE program (based on the CShM concept) was used for 1-3 to estimate the angular distortion from an ideal tetrahedron. The molecules of 1-3 are effectively separated, and the values of the shortest distance of cobalt-cobalt are 8.442(6) and 6.774(8) A for 1, 10.349(8) and 10.716(8) A for 2 and 6.7…
Quantification of pedogenic particles masked by geogenic magnetic fraction
2021
AbstractPedogenic magnetic fraction in soils is attributed to fine-grained particles, i.e. superparamagnetic grains. In the case of a strongly magnetic geogenic fraction, pedogenic magnetic contribution is hard to detect. To the best of our knowledge, detailed research into the masking of pedogenic superparamagnetic grains and quantification of this effect has not yet been carried out. The principal aim of our research is to quantify the influence of coarse-grained ferrimagnetic fraction on the detection of the superparamagnetic grains. In order to describe the masking phenomenon, volume and frequency-dependent magnetic susceptibility were determined on a set of laboratory prepared samples …
Dinuclear manganese(iii) complexes with bioinspired coordination and variable linkers showing weak exchange effects: a synthetic, structural, spectro…
2019
Three dimanganese(iii) complexes have been synthesised and fully characterised by standard spectroscopic methods and spectroelectrochemistry. Each MnIII ion is chelated by a salen type ligand (H2L), but there is variation in the bridging group: LMn(OOCCH[double bond, length as m-dash]CHCOO)MnL, LMn(OOCC6H4COO)MnL, and LMn(OOCC6H4C6H4COO)MnL. X-ray diffraction revealed an axial compression of each six-coordinate high-spin d4 MnIII ion, which is a Jahn-Teller-active ion. Temperature dependent magnetic susceptibility and variable temperature-variable field (VTVH) magnetisation measurements, as well as high-frequency and -field EPR (HFEPR) spectroscopy were used to accurately describe the magne…
Optical and magnetic properties of ZnCoO thin films synthesized by electrodeposition
2008
Ternary Zn1−xCoxO crystalline films with different compositions were grown by electrodeposition. The Co content in the final compound is linked to the initial Co/Zn ratio in the starting solution. X-ray diffraction reveals a wurtzite structure for the Zn1−xCoxO films. Transmittance spectra show two effects proportional to Co content, a redshift of the absorption edge and three absorption bands, which are both interpreted to be due to the Co incorporated into the ZnO lattice. The amount of deposited charge was used to get a precise control of the film thickness. Magnetic measurements point out that Co(II) ions are isolated from each other, and consequently the films are paramagnetic. Francis…
Magnetic properties of the TbMn2 single crystals
1999
Abstract Single crystals of TbMn 2 were grown by the Czochralski method from a levitated melt. Results of electrical resistivity, magnetization in strong magnetic fields along the principal crystallographic directions, AC and DC magnetic susceptibility and the temperature dependence of the lattice parameter are presented.