Search results for "Ferromagnetic"
showing 10 items of 81 documents
Gilbert damping of CoFe-alloys
2019
We report structural, magnetic and dynamic properties of polycrystalline Coalt;subagt;xalt;/subagt;Fealt;subagt;1-xalt;/subagt;-alloy films on Sapphire, Silicon and MgO substrates across the full composition range, by using a Vector Network Analyser ferromagnetic resonance measurement technique (VNA-FMR), Superconducting Quantum Interference Device magnetometry (SQUID) and X-Ray Diffraction (XRD). In the approximate vicinity of 28% Co, we observe a minimum of the damping parameter, associated with a reduction in the density of states to a minimum value at the Fermi energy level. For films on all substrates, we find magnetic damping of the order of 4-5⋅10alt;supagt;-3alt;/supagt;, showing th…
Hydrogen bonding versus π-stacking in ferromagnetic interactions. Studies on a copper triazolopyridine complex
2013
Magnetic susceptibility measurements show weak ferromagnetic exchange between the copper(II) ions of a novel triazolopyridine derivative [Cu(TPT)(H2O)2(BF4)](BF4)·2H2O (TPT = 3-{6-([1,2,3]triazolo[1,5-a]pyrid-3-yl)-2-pyridyl}-[1,2,3]triazolo[1,5-a]pyridine). Mononuclear [Cu(TPT)(H2O)2(BF4)]+ entities are connected through O–H⋯F, C–H⋯F and π⋯π interactions to give a 3D framework. Ferromagnetic properties are discussed on the basis of the interactions network.
Flexible ferromagnetic filaments and the interface with biology
2009
Flexible ferromagnetic filaments are studied both theoretically and experimentally. Two main deformation modes of the filament at magnetic field inversion are theoretically described and observed experimentally by using DNA-linked chains of ferromagnetic particles. Anomalous orientation of ferromagnetic filaments perpendicular to AC field with a frequency which is high enough is predicted and confirmed experimentally. By experimental studies of magnetotactic bacteria it is demonstrated how these properties of ferromagnetic filaments may be used to measure the flexibility of the chain of magnetosomes.
A field induced ferromagnetic-like transition below 2.8 K in Li2CuO2: An experimental and theoretical study
1998
The low temperature magnetic properties of the Li2CuO2 compound have been investigated by means of superconducting quantum interference device magnetometry. We find in addition to an antiferromagnetic phase below 9.5 K a ferromagnetic-like steep rise of the magnetization around 2.8 K. The observed low temperature behavior is discussed by considering second and fourth order magnetocrystalline effective anisotropy coefficients, in addition to the exchange couplings reported in the literature. Work at the Institut de Ciencia dels Materials was supported by the Spanish Comisión Interministerial de Ciencia y Technología Grant No. CICYT MAT 96-1037.
Deformation of flexible ferromagnetic filaments under a rotating magnetic field
2020
This repository contains experimental data and images related to the publication: A. Zaben, G. Kitenbergs, A. Cēbers (2020) Deformation of flexible ferromagnetic filaments under a rotating magnetic field. Journal of Magnetism and Magnetic Materials, 499, 166233 https://doi.org/10.1016/j.jmmm.2019.166233 / https://arxiv.org/abs/1908.02604. Excel files are results named corresponding to figure number in the publication. Root file '1' is for experimental images used for Fig.3, 4 and 5; where either the length is constant having file names as the value of the field strength or named with length values with fixed field strength for different frequencies. The images are named as …
3D motion of flexible ferromagnetic filaments under rotating magnetic field
2020
This repository contains experimental data and numerical results related to the publication: A. Zaben, G. Kitenbergs, A. Cēbers (2020), 3D motion of flexible ferromagnetic filaments under rotating magnetic field. Soft Matter, https://doi.org/10.1039/D0SM00403K / https://arxiv.org/abs/2003.03737. Figs_data.xlsx contains the data presented in the figures. Experimental_Data.rar contains experimental images used to obtain the results for Fig. 3 and 9. The files are named with the operating frequency, field strength and filament length. Numerical.rar contains numerical results used in Fig.6, 8 and 9. The files are named with Cm values. The results are in .dat files named with Cm values follo…
Room-temperature spin-orbit torque in NiMnSb
2015
Materials that crystalize in diamond-related lattices, with Si and GaAs as their prime examples, are at the foundation of modern electronics. Simultaneously, the two atomic sites in the unit cell of these crystals form inversion partners which gives rise to relativistic non-equilibrium spin phenomena highly relevant for magnetic memories and other spintronic devices. When the inversion-partner sites are occupied by the same atomic species, electrical current can generate local spin polarization with the same magnitude and opposite sign on the two inversion-partner sites. In CuMnAs, which shares this specific crystal symmetry of the Si lattice, the effect led to the demonstration of electric…
The key role of hydrogen bonding in the nuclearity of three copper(II) complexes with hydrazone-derived ligands and nitrogen donor heterocycles
2011
International audience; Three new Cu(II) complexes of formula [Cu(L1)(pyz)(CH3OH)]ClO4 (1), [Cu(L1)(4,4′-bpy)(ClO4)]·0.5H2O (2) and [{Cu(L2)(ClO4)}2(μ-4,4′-bpy)] (3) have been synthesised by using pyrazine (pyz) and 4,4′-bipyridine (4,4′-bpy) and tridentate O,N,O-donor hydrazone ligands, L1H and L2H, obtained by the condensation of 1,1,1-trifluoro-2,4-pentanedione with salicyloylhydrazide and benzhydrazide, respectively. The ligands and their complexes have been characterized by elemental analyses, FT-IR, and UV–Vis spectroscopies. Single crystal X-ray structure analysis evidences the metal ion in a slightly deformed square pyramidal geometry in all the complexes. However complexes 1 and 2 …
Spin canting in Re(IV) complexes: magnetic properties of [ReX4(bpym)] ( X = Cl and Br; bpym = 2,2′-bipyrimidine)
2008
The mononuclear complexes [ReCl4(bpym)] (1) and [ReBr4(bpym)] (2) (bpym = 2,2′-bipyrimidine) are weak ferromagnets. Magnetic ordering occurs below 7.0 (1) and 20.0 K (2) and good hysteresis loops are observed for the two compounds at 2.0 K. A spin-canting phenomenon, i.e., a non-strict linearity of the individual spins aligned in an anti-parallel way by intermolecular antiferromagnetic coupling occurring in many Re(IV) complexes, accounts for these magnetic features which are unusual in molecular solids such as 1 and 2.
A novel high-spin heterometallic Ni12K4cluster incorporating large Ni–azide circles and an in situ cyanomethylated di-2-pyridyl ketone
2005
Reaction of di-2-pyridyl ketone (dpk) with nickel acetate and azide in the presence of potassium tert-butylate as a catalytic base generates the title compound, which contains the largest [Ni(m1,1-N3)]6 circles in the discrete ferromagnetically-coupled MII–azide cluster family, and shows an unprecedented in situ cyanomethylation of ketone. Clemente Juan, Juan Modesto, Juan.M.Clemente@uv.es