Manganese(II) complexes with croconate and 2-(2-pyridyl)imidazole ligands: Syntheses, X-ray structures and magnetic properties

Thin films nanoparticles TbxY3-xFe5O12 (x=0.0, 1.0, 2.0) were prepared by the sol-gel process followed by annealing process at various annealing temperatures of 700° C, 800° C and 900° C in air for 2 h. The results obtained from X-ray diffractometer (XRD) show that the films annealed below 900°C exhibit peaks of garnet mixed with small amounts of YFeO3 and Fe2O3. Pure garnet phase has been detected in the films annealed at 900°C. Before annealing the films show amorphous structures. The particles sizes measurement using the field emission scanning electron microscope (FE-SEM) showed that the particles sizes increased as the annealing temperature increased. The magnetic properties were measured at room temperature using the vibrating sample magnetometer (VSM). The saturation magnetization (Ms) of the films also increased with the annealing temperature. However, different behavior of coercivity (Hc) has been observed as the annealing temperature was increased.

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Reversible magnetism switching of iron oxide nanoparticle dispersions by controlled agglomeration

Nanoscale Advances ◽

10.1039/d1na00159k ◽

2021 ◽

Author(s):

Stephan Müssig ◽

Björn Kuttich ◽

Florian Fidler ◽

Daniel Haddad ◽

Susanne Wintzheimer ◽

...

Keyword(s):

Magnetic Properties ◽

Iron Oxide ◽

Light Scattering ◽

Superparamagnetic Iron Oxide ◽

Iron Oxide Nanoparticle ◽

Oxide Nanoparticles ◽

X Ray ◽

X Ray Scattering ◽

Nanoparticle Dispersions ◽

Oxide Nanoparticle

The controlled agglomeration of superparamagnetic iron oxide nanoparticles (SPIONs) was used to rapidly switch their magnetic properties. Small-angle X-ray scattering (SAXS) and dynamic light scattering showed that tailored iron oxide...

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(thf)2Ln(Ge9{Si(SiMe3)3}3)2 (Ln = Eu, Sm): the first coordination of metalloid germanium clusters to lanthanides

Chemical Communications ◽

10.1039/d1cc01151k ◽

2021 ◽

Author(s):

Andreas Schnepf ◽

Svetlana Klementyeva ◽

Claudio Schrenk ◽

Marat M Khusniyarov ◽

Minghui Zhang

Keyword(s):

Magnetic Properties ◽

Rare Earth ◽

Crystallographic Analysis ◽

Rare Earth Complexes ◽

Group 14 ◽

X Ray ◽

Germanium Clusters

We report the synthesis, structure and magnetic properties of the first rare earth complexes of metalloid group 14 clusters [(thf)2Ln(Ge9Hyp3)2] (Ln = Eu, Sm, Hyp = Si(SiMe3)3). X-ray crystallographic analysis...

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Al-driven peculiarities of local coordination and magnetic properties in single-phase Alx-CrFeCoNi high-entropy alloys

Nano Research ◽

10.1007/s12274-021-3704-5 ◽

2021 ◽

Author(s):

Alevtina Smekhova ◽

Alexei Kuzmin ◽

Konrad Siemensmeyer ◽

Chen Luo ◽

Kai Chen ◽

...

Keyword(s):

Magnetic Properties ◽

Single Phase ◽

Magnetic Circular Dichroism ◽

Surface Region ◽

Face Centered Cubic ◽

X Rays ◽

X Ray ◽

High Entropy ◽

X Ray Absorption ◽

Absorption Edges

AbstractModern design of superior multi-functional alloys composed of several principal components requires in-depth studies of their local structure for developing desired macroscopic properties. Herein, peculiarities of atomic arrangements on the local scale and electronic states of constituent elements in the single-phase face-centered cubic (fcc)- and body-centered cubic (bcc)-structured high-entropy Alx-CrFeCoNi alloys (x = 0.3 and 3, respectively) are explored by element-specific X-ray absorption spectroscopy in hard and soft X-ray energy ranges. Simulations based on the reverse Monte Carlo approach allow to perform a simultaneous fit of extended X-ray absorption fine structure spectra recorded at K absorption edges of each 3d constituent and to reconstruct the local environment within the first coordination shells of absorbers with high precision. The revealed unimodal and bimodal distributions of all five elements are in agreement with structure-dependent magnetic properties of studied alloys probed by magnetometry. A degree of surface atoms oxidation uncovered by soft X-rays suggests different kinetics of oxide formation for each type of constituents and has to be taken into account. X-ray magnetic circular dichroism technique employed at L2.3 absorption edges of transition metals demonstrates reduced magnetic moments of 3d metal constituents in the sub-surface region of in situ cleaned fcc-structured Al0.3-CrFeCoNi compared to their bulk values. Extended to nanostructured versions of multicomponent alloys, such studies would bring new insights related to effects of high entropy mixing on low dimensions.

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Synthesis, spectroscopic characterization, X-ray structure and magnetic properties of [Cu(hmquin-7-COOH)2(MeOH)] complex

Polyhedron ◽

10.1016/j.poly.2009.07.057 ◽

2009 ◽

Vol 28 (17) ◽

pp. 3774-3780 ◽

Cited By ~ 3

Author(s):

B. Machura ◽

A. Świtlicka ◽

J. Mroziński ◽

J. Kłak ◽

R. Kruszynski ◽

...

Keyword(s):

Magnetic Properties ◽

Spectroscopic Characterization ◽

X Ray

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Green synthesis and characterization of hexaferrite strontium-perovskite strontium photocatalyst nanocomposites

Main Group Metal Chemistry ◽

10.1515/mgmc-2020-0004 ◽

2020 ◽

Vol 43 (1) ◽

pp. 26-42 ◽

Cited By ~ 2

Author(s):

Zahra Hajian Karahroudi ◽

Kambiz Hedayati ◽

Mojtaba Goodarzi

Keyword(s):

Magnetic Properties ◽

Green Synthesis ◽

Sol Gel ◽

Synthesis Method ◽

Combustion Method ◽

Lemon Juice ◽

X Ray Diffraction ◽

X Ray ◽

Auto Combustion

AbstractThis study presents a preparation of SrFe12O19– SrTiO3 nanocomposite synthesis via the green auto-combustion method. At first, SrFe12O19 nanoparticles were synthesized as a core and then, SrTiO3 nanoparticles were prepared as a shell for it to manufacture SrFe12O19–SrTiO3 nanocomposite. A novel sol-gel auto-combustion green synthesis method has been used with lemon juice as a capping agent. The prepared SrFe12O19–SrTiO3 nanocomposites were characterized by using several techniques to characterize their structural, morphological and magnetic properties. The crystal structures of the nanocomposite were investigated via X-ray diffraction (XRD). The morphology of SrFe12O19– SrTiO3 nanocomposite was studied by using a scanning electron microscope (SEM). The elemental composition of the materials was analyzed by an energy-dispersive X-ray (EDX). Magnetic properties and hysteresis loop of nanopowder were characterized via vibrating sample magnetometer (VSM) in the room temperature. Fourier transform infrared spectroscopy (FTIR) spectra of the samples showed the molecular bands of nanoparticles. Also, the photocatalytic behavior of nanocomposites has been checked by the degradation of azo dyes under irradiation of ultraviolet light.

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Effects of Perpendicular Magnetic Field Annealing on the Structural and Magnetic Properties of [Co/Ni]2/PtMn Thin Films

Magnetochemistry ◽

10.3390/magnetochemistry7030038 ◽

2021 ◽

Vol 7 (3) ◽

pp. 38

Author(s):

Roshni Yadav ◽

Chun-Hsien Wu ◽

I-Fen Huang ◽

Xu Li ◽

Te-Ho Wu ◽

...

Keyword(s):

Magnetic Field ◽

Thin Films ◽

Magnetic Properties ◽

Photoelectron Spectroscopy ◽

Perpendicular Magnetic Field ◽

Face Centered Cubic ◽

Lattice Image ◽

X Ray ◽

Field Annealing ◽

Face Centered

In this study, [Co/Ni]2/PtMn thin films with different PtMn thicknesses (2.7 to 32.4 nm) were prepared on Si/SiO2 substrates. The post-deposition perpendicular magnetic field annealing (MFA) processes were carried out to modify the structures and magnetic properties. The MFA process also induced strong interlayer diffusion, rendering a less sharp interface between Co and Ni and PtMn layers. The transmission electron microscopy (TEM) lattice image analysis has shown that the films consisted of face-centered tetragonal (fct) PtMn (ordered by MFA), body-centered cubic (bcc) NiMn (due to intermixing), in addition to face-centered cubic (fcc) Co, Ni, and PtMn phases. The peak shift (2-theta from 39.9° to 40.3°) in X-ray diffraction spectra also confirmed the structural transition from fcc PtMn to fct PtMn after MFA, in agreement with those obtained by lattice images in TEM. The interdiffusion induced by MFA was also evidenced by the depth profile of X-ray photoelectron spectroscopy (XPS). Further, the magnetic properties measured by vibrating sample magnetometry (VSM) have shown an increased coercivity in MFA-treated samples. This is attributed to the presence of ordered fct PtMn, and NiMn phases exchange coupled to the ferromagnetic [Co/Ni]2 layers. The vertical shift (Mshift = −0.03 memu) of the hysteresis loops is ascribed to the pinned spins resulting from perpendicular MFA processes.

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The Study of Magnetic Properties for Non-Magnetic Ions Doped BiFeO3

Materials ◽

10.3390/ma14154061 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4061

Author(s):

Yongtao Li ◽

Liqing Liu ◽

Dehao Wang ◽

Hongguang Zhang ◽

Xuemin He ◽

...

Keyword(s):

Magnetic Properties ◽

Local Structure ◽

Metal Ion ◽

Single Phase ◽

Sol Gel ◽

X Ray ◽

Co Doping ◽

Magnetic Ions ◽

X Ray Absorption ◽

Fe Ions

BiFeO3 is considered as a single phase multiferroic. However, its magnetism is very weak. We study the magnetic properties of BiFeO3 by Cu and (Cu, Zn). Polycrystalline samples Bi(Fe0.95Cu0.05)O3 and BiFe0.95(Zn0.025Cu0.025)O3 are prepared by the sol-gel method. The magnetic properties of BiFe0.95(Zn0.025Cu0.025)O3 are greater than that of BiFeO3 and Bi(Fe0.95Cu0.05)O3. The analyses of X-ray absorption fine structure data show that the doped Cu atoms well occupy the sites of the Fe atoms. X-ray absorption near edge spectra data confirm that the valence state of Fe ions does not change. Cu and Zn metal ion co-doping has no impact on the local structure of the Fe and Bi atoms. The modification of magnetism by doping Zn can be understood by the view of the occupation site of non-magnetically active Zn2+.

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Influence of Li2CO3 addition on electrical and magnetic properties of Ni0.6Mg0.4Fe2O4

Journal of Advanced Dielectrics ◽

10.1142/s2010135x20500034 ◽

2020 ◽

Vol 10 (03) ◽

pp. 2050003

Author(s):

M. R. Hassan ◽

M. T. Islam ◽

M. N. I. Khan

Keyword(s):

Magnetic Properties ◽

Single Phase ◽

Low Frequency ◽

Solid State Reaction Method ◽

Charge Carriers ◽

X Ray Diffraction ◽

X Ray ◽

Electrical And Magnetic Properties ◽

Frequency Regime ◽

Xrd Patterns

In this research, influence of adding Li2CO3 (at 0%, 2%, 4%, 6%) on electrical and magnetic properties of [Formula: see text][Formula: see text]Fe2O4 (with 60% Ni and 40% Mg) ferrite has been studied. The samples are prepared by solid state reaction method and sintered at 1300∘C for 6[Formula: see text]h. X-ray diffraction (XRD) patterns show the samples belong to single-phase cubic structure without any impurity phase. The magnetic properties (saturation magnetization and coercivity) of the samples have been investigated by VSM and found that the higher concentration of Li2CO3 reduces the hysteresis loss. DC resistivity increases with Li2CO3 contents whereas it decreases initially and then becomes constant at lower value with temperature which indicates that the studied samples are semiconductor. The dielectric dispersion occurs at a low-frequency regime and the loss peaks are formed in a higher frequency regime, which are due to the presence of resonance between applied frequency and hopping frequency of charge carriers. Notably, the loss peaks are shifted to the lower frequency with Li2CO3 additions.

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Synthesis, X-ray Studies and Magnetic Properties of Dinuclear NiII and CuII Complexes Bridged by the Azo-2,2′-bipyridine Ligand

European Journal of Inorganic Chemistry ◽

10.1002/ejic.200390131 ◽

2003 ◽

Vol 2003 (5) ◽

pp. 988-994 ◽

Cited By ~ 19

Author(s):

Cristian S. Campos-Fernández ◽

José R. Galán-Mascarós ◽

Bradley W. Smucker ◽

Kim R. Dunbar

Keyword(s):

Magnetic Properties ◽

X Ray ◽

Bipyridine Ligand

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