FMR study of samples obtained by nitriding and nitrides reduction of nanocrystalline iron

AbstractSamples obtained by nitriding of promoted nanocrystalline iron and the nitrides reduction at various nitriding potential in terms of thermodynamic parameters were investigated by electron paramagnetic resonance/ferromagnetic resonance (EPR/FMR) method at room temperature. Experimental FMR spectra were fitted by the Dysonian-type resonance lines arising from the presence of different Fe–N phases. The obtained FMR parameters allowed us to identify the component phases and to determine their magnetic properties. In general, the proposed simple method of decomposition of the FMR spectra produced results on the phase content in investigated samples that were consistent with XRD measurements and additionally, magnetic characteristics of the studied nanomagnets.

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Monitoring of the Mechanism of Mn Ions Incorporation into Quantum Dots by Optical and EPR Spectroscopy

Photonics ◽

10.3390/photonics6040107 ◽

2019 ◽

Vol 6 (4) ◽

pp. 107

Author(s):

Yuriy G. Galyametdinov ◽

Dmitriy O. Sagdeev ◽

Andrey A. Sukhanov ◽

Violeta K. Voronkova ◽

Radik R. Shamilov

Keyword(s):

Electron Paramagnetic Resonance ◽

Magnetic Properties ◽

Luminescent Properties ◽

Manganese Concentration ◽

Manganese Ions ◽

Paramagnetic Resonance ◽

Synthesis Of Nanoparticles ◽

Zinc Sulfide Nanoparticles ◽

Optical And Magnetic Properties ◽

Electron Paramagnetic

Synthesis of nanoparticles doped with various ions can significantly expand their functionality. The conditions of synthesis exert significant influence on the distribution nature of doped ions and therefore the physicochemical properties of nanoparticles. In this paper, a correlation between the conditions of synthesis of manganese-containing cadmium sulfide or zinc sulfide nanoparticles and their optical and magnetic properties is analyzed. Electron paramagnetic resonance was used to study the distribution of manganese ions in nanoparticles and the intensity of interaction between them depending on the conditions of synthesis of nanoparticles, the concentration of manganese, and the type of initial semiconductor. The increase of manganese concentration is shown to result in the formation of smaller CdS-based nanoparticles. Luminescent properties of nanoparticles were studied. The 580 nm peak, which is typical for manganese ions, becomes more distinguished with the increase of their concentration and the time of synthesis.

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Temperature Dependent Line-Shape of the Silicon Dangling Bond EPR-Resonance in Polycrystalline Silicon

MRS Proceedings ◽

10.1557/proc-452-1019 ◽

1996 ◽

Vol 452 ◽

Cited By ~ 1

Author(s):

N. H. Nickel ◽

E. A. Schiff

Keyword(s):

Electron Paramagnetic Resonance ◽

Polycrystalline Silicon ◽

Room Temperature ◽

Dangling Bond ◽

Temperature Dependent ◽

Paramagnetic Resonance ◽

Temperature Electron ◽

Motional Narrowing ◽

G Value ◽

Electron Paramagnetic

AbstractThe temperature dependence of the silicon dangling-bond resonance in polycrystalline (poly-Si) and amorphous silicon (a-Si:H) was measured. At room temperature, electron paramagnetic resonance (EPR) measurements reveal an isotropie g-value of 2.0055 and a line width of 6.5 and 6.1 G for Si dangling-bonds in a-Si:H and poly-Si, respectively. In both materials spin density and g-value are independent of temperature. While in a-Si:H the width of the resonance did not change with temperature, poly-Si exhibits a remarkable T dependence of ΔHpp. In unpassivated poly-Si a pronounced decrease of ΔHpp is observed for temperatures above 300 K. At 384 K ΔHpp reaches a minimum of 5.1 G, then increases to 6.1 G at 460 K, and eventually decreases to 4.6 G at 530 K. In hydrogenated poly-Si ΔHpp decreases monotonically above 425 K. The decrease of ΔHpp is attributed to electron hopping causing motional narrowing. An average hopping distance of 15 and 17.5 Å was estimated for unhydrogenated and H passivated poly-Si, respectively.

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EPR Spectra of Sintered Cd1−xCrxTe Powdered Crystals with Various Cr Content

Materials ◽

10.3390/ma14133449 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3449

Author(s):

Ireneusz Stefaniuk ◽

Werner Obermayr ◽

Volodymyr D. Popovych ◽

Bogumił Cieniek ◽

Iwona Rogalska

Keyword(s):

Curie Temperature ◽

Room Temperature ◽

Integral Intensity ◽

Resonance Field ◽

Epr Spectra ◽

Paramagnetic Resonance ◽

Simple Method ◽

Paramagnetic Curie Temperature ◽

Cr Content ◽

Electron Paramagnetic

In this paper, we show a simple method of producing ferromagnetic materials with a Curie temperature above room temperature. The electron paramagnetic resonance (EPR) spectra of Cd1−xCrxTe (0.002 < x < 0.08) were measured with a dependence on temperature (82 K < T < 381 K). Obtained EPR lines were fitted to a Lorentz-shaped curve. The temperature dependencies of the parameters of the EPR lines, such as the peak-to-peak linewidth (Hpp), the intensity (A), as well as the resonance field (Hr), were studied. Ferromagnetism was noticed in samples at high temperatures (near room temperature). For a sample with a nominal concentration of chrome of x = 0.05, a very strong intrinsic magnetic field is observed. The value of the effective gyromagnetic factor for this sample is ge = 30 at T = 240 K. An increase of chrome concentration above x = 0.05 reduces the ferromagnetic properties considerably. Analysis of the temperature dependencies of the integral intensity of EPR spectra was carried out using the Curie–Weiss law and the paramagnetic Curie temperature was obtained.

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Room Temperature Electron Paramagnetic Resonance (EPR) Signal Storage

10.1109/gmtt.1969.1122717 ◽

1969 ◽

Author(s):

D.A. Bozanic ◽

D.C. Buck ◽

F.H. Harris ◽

R.E. Huber ◽

D. Mergerian ◽

...

Keyword(s):

Electron Paramagnetic Resonance ◽

Room Temperature ◽

Paramagnetic Resonance ◽

Temperature Electron ◽

Epr Signal ◽

Electron Paramagnetic

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Paramagnetic Defects in Benitoite

Zeitschrift für Naturforschung A ◽

10.1515/zna-1991-0703 ◽

1991 ◽

Vol 46 (7) ◽

pp. 579-582 ◽

Cited By ~ 1

Author(s):

A. B. Vassilikou-Dova ◽

K. Eftaxias

Keyword(s):

Electron Paramagnetic Resonance ◽

Hyperfine Interaction ◽

Relative Intensity ◽

Room Temperature ◽

Paramagnetic Resonance ◽

Electron Paramagnetic ◽

Magnetic Defects

Abstract In clear, blue, transparent bipyramidal crystals of the rare mineral benitoite, BaTiSi3O9, para magnetic defects have been investigated by electron paramagnetic resonance at room temperature and 9.43 GHz. They are attributed to Sn3+ and Fe3+ . A pair of satellites recorded for a wide angular rage around B0 || c (~40°) and a relative intensity of ~ 13% to the central signal is most likely due to hyperfine interaction with 117Sn and 119Sn isotopes. Attempts to bleach the colour of the crystal were unsuccessful.

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Electron Paramagnetic Resonance Spectroscopic Investigation of the Dynamics of Spin Probe in Room Temperature Ionic Liquid

Modern Chemistry & Applications ◽

10.4172/2329-6798.1000189 ◽

2016 ◽

Vol 04 (04) ◽

Author(s):

Arijit Sengupta ◽

Kadam RM

Keyword(s):

Electron Paramagnetic Resonance ◽

Ionic Liquid ◽

Spectroscopic Investigation ◽

Spin Probe ◽

Room Temperature ◽

Room Temperature Ionic Liquid ◽

Paramagnetic Resonance ◽

Electron Paramagnetic

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Transient electron paramagnetic resonance of the triplet state of P700 in photosystem I: Evidence for triplet delocalization at room temperature

Biochemistry ◽

10.1021/bi00069a020 ◽

1993 ◽

Vol 32 (18) ◽

pp. 4842-4847 ◽

Cited By ~ 30

Author(s):

Ina Sieckmann ◽

Klaus Brettel ◽

Christian Bock ◽

Arthur van der Est ◽

Dietmar Stehlik

Keyword(s):

Electron Paramagnetic Resonance ◽

Triplet State ◽

Photosystem I ◽

Room Temperature ◽

Paramagnetic Resonance ◽

Electron Paramagnetic

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Димерная самоорганизация примесных ионов эрбия в синтетическом форстерите

Физика твердого тела ◽

10.21883/ftt.2019.02.47131.227 ◽

2019 ◽

Vol 61 (2) ◽

pp. 313

Author(s):

Р.Б. Зарипов ◽

Л.В. Мингалиева ◽

В.Ф. Тарасов ◽

Е.В. Жариков ◽

К.А. Субботин ◽

...

Keyword(s):

Electron Paramagnetic Resonance ◽

Resonance Method ◽

Magnetic Characteristics ◽

Spin Interaction ◽

Magnesium Ions ◽

Crystallographic Position ◽

Paramagnetic Resonance ◽

Effective Spin ◽

Erbium Ions ◽

Electron Paramagnetic

AbstractThe electron paramagnetic resonance spectra of impurity trivalent erbium ions in synthetic forsterite single crystals (Mg_2SiO_4) have been studied by the electron paramagnetic resonance method in the X and Q frequency bands. It is found that erbium ions predominantly substitute for magnesium ions in crystallographic position M1 that is characterized by the inversion symmetry of the crystal field. In this case, a pronounced effect of dimer self-organization of erbium ions during the crystal growth takes place; the effect is manifested in the fact that the concentration of erbium dimer associates consisting of two closely spaced ions bound by the spin– spin interaction is several orders of magnitude higher than the concentration of dimer associates that form randomly at a statistical distribution of impurity ions in the forsterite crystal lattice. The directions of the main magnetic axes and the parameters of the effective spin Hamiltonian describing the magnetic characteristics of impurity erbium centers have been determined.

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