scholarly journals Mössbauer Spectroscopy, Structural and Magnetic Studies of Zn2+Substituted Magnesium Ferrite Nanomaterials Prepared by Sol-Gel Method

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Yun He ◽  
Xingxing Yang ◽  
Jinpei Lin ◽  
Qing Lin ◽  
Jianghui Dong
Keyword(s):  
Saturation Magnetization ◽  
Room Temperature ◽  
Mössbauer Spectra ◽  
Zinc Concentration ◽  
Sol Gel ◽  
Magnetic Interactions ◽  
Magnesium Ferrite ◽  
Magnetic Studies ◽  
Mossbauer Spectra ◽  
Absorption Area

Zinc substituted magnesium ferrite nanomaterialsMg1-xZnxFe2O4(x= 0, 0.1, 0.3, 0.5, 0.7) powders have been prepared by a sol-gel autocombustion method. The lattice parameter increases with increase in Zn concentration, but average crystallite size tends to decrease by increasing the zinc content. SEM results indicate the distribution of grains and morphology of the samples. Some particles are agglomerated due to the presence of magnetic interactions among particles. Room temperature Mössbauer spectra ofMg1-xZnxFe2O4shows that the A Mössbauer absorption area decreases and the B Mössbauer absorption area increases with zinc concentration increasing. The change of the saturation magnetization can be explained with Néel’s theory. It was confirmed that the transition from ferrimagnetic to superparamagnetic behaviour depends on increase in zinc concentration by Mössbauer spectra at room temperature. Saturation magnetization increases and coercivity decreases with Zn content increasing.

scholarly journals Manganese/Yttrium Codoped Strontium Nanohexaferrites: Evaluation of Magnetic Susceptibility and Mossbauer Spectra

Nanomaterials ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 24 ◽  
Author(s):  
Munirah Almessiere ◽  
Yassine Slimani ◽  
Hakan Güngüneş ◽  
Abdulhadi Baykal ◽  
S.V. Trukhanov ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Mössbauer Spectra ◽  
Ac Susceptibility ◽  
Sol Gel ◽  
Hyperfine Magnetic Field ◽  
Analytical Techniques ◽  
Magnetic Interactions ◽  
Mossbauer Spectra

Manganese (Mn)- and yttrium (Y)-substituted Sr-nanohexaferrites (MYSNHFs) of composition Sr1−xMnxFe12−xYxO19 (with 0.0 ≤ x ≤ 0.5) were prepared by citrate sol-gel autocombustion method. As-prepared MYSNHFs were characterized via diverse analytical techniques to determine the influence of Mn and Y cosubstitution on their microstructures and magnetic properties. 57Fe Mössbauer spectra of the MYSNHFs were used to evaluate the variation in the line width, isomer shift, quadrupole splitting, and hyperfine magnetic field values. It was shown that the dopant ions could preferentially occupy the 12k, 4f2, and 2b sites. Furthermore, the observed shift in the blocking temperatures of the studied MYSNHFs towards lower values with rising Mn2+ and Y3+ contents was attributed to the overall particles size reduction. Meanwhile, the AC susceptibility of the proposed MYSNHFs revealed that the magnetic interactions were weakened with the increase in dopant contents which was ascribed to the replacement of both Sr2+ and Fe3+ ions by the Mn2+ and Y3+ dopants.

Electronic and magnetic states of Fe ions in the Co2FeBO5

2021 ◽  
Author(s):  
Natalia Kazak ◽  
Yurii V. Knyazev ◽  
Vyacheslav Zhandun ◽  
Juan Bartolomé ◽  
Ana Arauzo ◽  
...  
Keyword(s):  
Mössbauer Spectroscopy ◽  
Room Temperature ◽  
Mössbauer Spectra ◽  
Mossbauer Spectroscopy ◽  
57Fe Mössbauer Spectroscopy ◽  
57Fe Mössbauer ◽  
Mossbauer Spectra ◽  
57Fe Mossbauer Spectroscopy ◽  
Magnetic States ◽  
Fe Ions

The ludwigite Co2FeBO5 has been studied experimentally using 57Fe Mössbauer spectroscopy and theoretically by means of the DFT+GGA calculations. The room-temperature Mössbauer spectra are composed of four quadrupole doublets corresponding...

scholarly journals Synthesis of Cu and Ce co-doped ZnO nanoparticles: crystallographic, optical, molecular, morphological and magnetic studies

2017 ◽  
Vol 35 (2) ◽  
pp. 427-434 ◽  
Author(s):  
Mohit Rawat ◽  
Jasmeet Singh ◽  
Jagpreet Singh ◽  
Chamkaur Singh ◽  
Amritpal Singh ◽  
...  
Keyword(s):  
Room Temperature ◽  
Sol Gel ◽  
Research Work ◽  
Yellow Emission ◽  
Near Band Edge ◽  
Band Edge Emission ◽  
Ferromagnetic Behavior ◽  
Magnetic Studies ◽  
Transmission Electron Microscopy Analysis ◽  
Co Doped

Abstract In the present research work, crystallographic, optical, molecular, morphological and magnetic properties of Zn1-xCuxO (ZnCu) and Zn1-x-yCeyCuxO (ZnCeCu) nanoparticles have been investigated. Polyvinyl alcohol (PVA) coated ZnCu and ZnCeCu nanoparticles have been synthesized by chemical sol-gel method and thoroughly studied using various characterization techniques. X-ray diffraction pattern indicates the wurtzite structure of the synthesized ZnCu and ZnCeCu particles. Transmission electron microscopy analysis shows that the synthesized ZnCu and ZnCeCu particles are of spherical shape, having average sizes of 27 nm and 23 nm, respectively. The incorporation of Cu and Ce in the ZnO lattice has been confirmed through Fourier transform infrared spectroscopy. Room temperature photoluminescence spectra of the ZnO doped with Cu and co-doped Ce display two emission bands, predominant ultra-violet near-band edge emission at 409.9 nm (3 eV) and a weak green-yellow emission at 432.65 nm (2.27 eV). Room temperature magnetic study confirms the diamagnetic behavior of ZnCu and ferromagnetic behavior of ZnCeCu.

Study of structural, electrical, optical and magnetic properties of Hexaferrite–Polyaniline nanocomposites

2019 ◽  
Vol 33 (13) ◽  
pp. 1950134 ◽  
Author(s):  
Muhammad Ajmal ◽  
M. U. Islam
Keyword(s):  
Saturation Magnetization ◽  
In Situ Polymerization ◽  
Sol Gel ◽  
Electric Polarization ◽  
Room Temperature Resistivity ◽  
Magnetic Studies ◽  
Xrd Pattern ◽  
Gel Technique ◽  
Pani Matrix

Y-type hexagonal ferrite (CaBaCo2Ga[Formula: see text]Fe[Formula: see text]O[Formula: see text]) was synthesized by sol–gel technique. The ferrite–polymer composites (1−x)CaBaCo2Ga[Formula: see text]Fe[Formula: see text]O[Formula: see text]+(x)polyaniline (x=0.25, 0.50, 0.75, 1) namely PF1, PF2, PF3 and polyaniline (PANI) were synthesized by in situ polymerization. The synthesized samples were characterized by XRD, SEM, electrical and dielectric measurements, optical and magnetic studies. XRD pattern reveals a broad peak of polyaniline which is an indication of amorphous nature of PANI. Room-temperature resistivity increases from 2.14 × 101 [Formula: see text]cm to 2.78 × 10[Formula: see text]cm as ferrite content increases due to resistive behavior of the ferrite particles dispersed in the PANI matrix. The value of dielectric constant decreases at fixed frequency with increasing concentration of ferrite filler which is predominantly due to exchange of electrons between Fe[Formula: see text] and Fe[Formula: see text] ions that ultimately results in enhancement of electric polarization and conductivity. The optical bandgap increases with increasing amount of ferrite in the composites. The saturation magnetization and remanence increase with the increase of ferrite filler amount in PANI matrix whereas coercivity decreases. The decrease in coercivity and increase in saturation magnetization are related to Brown’s relation. The present nanocomposite samples may be the best candidates for electromagnetic shielding.

scholarly journals Investigation of Magnetic Ordering in RCo12B6 (R = Y, Nd) by 57Fe Mössbauer Spectroscopy

1993 ◽  
Vol 46 (5) ◽  
pp. 679 ◽  
Author(s):  
JM Cadogan ◽  
SJ Campbell ◽  
XL Zhao ◽  
E Wu
Keyword(s):  
Basal Plane ◽  
Room Temperature ◽  
Mössbauer Spectra ◽  
57Fe Mössbauer Spectroscopy ◽  
Magnetic Ordering ◽  
Spin Reorientation ◽  
57Fe Mössbauer ◽  
Mossbauer Spectra ◽  
57Fe Mossbauer Spectroscopy ◽  
Increasing Temperature

Mossbauer spectra of YC012B6 and NdCo12B6 doped with enriched 57Fe have been obtained at various temperatures between 4�2 K and room temperature. The spectrum of YC012B6 at 4�2 K indicates that the Co sublattice orders in the crystallographic basal plane. NdCo12B6 orders along or close to the crystallographic c-axis at 4�2 K and undergoes a spin-reorientation with increasing temperature until at ~55 K the magnetisation lies in or near the basal plane.

Preparation and Characterization of a Novel Gadolinium Triple-Decker Sandwich-Type Complex with Tetrabenzoporphyrin Ligand

2013 ◽  
Vol 690-693 ◽  
pp. 573-576
Author(s):  
Qi Feng Liu
Keyword(s):  
Room Temperature ◽  
Spectroscopic Properties ◽  
Magnetic Interactions ◽  
Antiferromagnetic Coupling ◽  
Magnetic Studies ◽  
Conjugated Systems ◽  
Type Complex ◽  
Vis Spectroscopy ◽  
Sandwich Type

A novel gadolinium triple-decker sandwich-type complex containing tetrabenzoporphyrin (TBP) ligands-Gd (TBP)3was prepared from porphyrin 1 and Gd (acac)3.nH2O in boiling 1, 2, 4-Tcb for 45~48 h under Ar. Its structure is characterized by Uv-Vis spectroscopy and HR-MS. The spectroscopic properties show that its longest-wavelength visible band (600-800 nm) is obviously red-shifted due to the extension of the π conjugated systems derived from the linear benzoannulation in the TBP ring. The magnetic studies also indicate that there is no magnetic interactions between two Gd (III) ions in the triple-deckers in the range from room temperature down to 20K and very weak antiferromagnetic coupling exists between two Gd (III) ions below 20K.

Room temperature Mössbauer spectra of 57Fe-doped La2SrCu2O6, La2CaCu2O6 and La1.6Sr0.4CaCu2O6

1991 ◽  
Vol 181 (1-3) ◽  
pp. 1-10 ◽  
Author(s):  
C. Meyer ◽  
F. Hartmann-Boutron ◽  
Y. Gros ◽  
P. Strobel
Keyword(s):  
Room Temperature ◽  
Mössbauer Spectra ◽  
Mossbauer Spectra

Preparation and Properties of Gadolinium Homoleptic Double-and Triple-Decker Complexes Containing Tetrabenzoporphyrin Ligand

2013 ◽  
Vol 750-752 ◽  
pp. 1816-1821
Author(s):  
Qi Feng Liu
Keyword(s):  
Room Temperature ◽  
Spin Exchange ◽  
Spectroscopic Studies ◽  
Magnetic Interactions ◽  
Antiferromagnetic Coupling ◽  
Ir Absorption ◽  
Magnetic Studies ◽  
Absorption Bands ◽  
Near Ir ◽  
Sandwich Type

Two novel gadolinium sandwich-type complexes containing tetrabenzoporphyrin (TBP) ligands-Gd (TBP)2and Gd (TBP)3were prepared from porphyrin 1 and Gd (acac)3. nH2O under Ar by boiling 1, 2, 4-Tcb for 15~17h and 45~48 h respectively. Their structures are characterized by Uv-Vis, HR-MS and IR. The spectroscopic studies show that their longest-wavelength visible and near-IR absorption bands are obviously red-shifted due to the extension of the π conjugated systems in the TBP ring. The magnetic studies indicate that the observed value of χMT for Gd (TBP)2is close to the combined value of Gd (III) and porphyrin radical anion at room temperature and that antiferromagnetic interaction possibly results from the intramolecular spin exchange between the porphyrin π-radical electron and that the gadolinium f unpaired electrons dominates its magnetic properties over the whole temperature range while there is no magnetic interactions between two Gd (III) ions in Gd (TBP)3in the range from room temperature down to 20K and very weak antiferromagnetic coupling exsits between two Gd (III) ions below 20K.

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