Structural Rietveld refinement and vibrational study of MgCr x Fe 2−x O 4 spinel ferrites

Sabri, K.; Rais, A.; Taïbî, K.; Moreau, Myriam; Ouddane, Baghdad; Addou, A.

doi:10.1016/j.physb.2016.08.011

Cited by 54 publications

(17 citation statements)

References 30 publications

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“…Ô (19) where F, MF, LP, AF and TF represent the structure factor, the multiplicity factor, Lorentz-Polarization factor, absorption factor and temperature factor respectively. The absorption (AF) and temperature (TF) factors vary in opposite directions with temperature and they were usually omitted especially for the problems where relative intensity calculations are concerned [23][24][25][26]. Therefore, equation (16) will be reduced to the following simple approximate form:…”

Section: Debye-waller Factor (Dwf)mentioning

confidence: 99%

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Effects of Zn Substitution on Structure Factors, Debye-Waller Factors and Related Structural Properties of the Mg1-xZnxFeNiO4 Spinels

Khalaf¹

2019

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The effects of Zn 2+ ions substitutions on the Debye-Waller Factors, structure factor and other related structural properties of the Mg 1-x Zn x NiFeO 4 (where 0.0≤x≤1.0) spinels have been investigated using the XRD, TEM, SEM and FT-IR tools. The Mg 1-x Zn x NiFeO 4 samples were prepared using the conventional ceramic solid state sintering techniques at temperatures around 1100°C. The Mg 1-x Zn x NiFeO 4 spinels have predominantly inverse type structure with inversion factor, λ in the range 0.69 to 0.36. The X-ray diffraction (XRD) patterns of all compositions showed the formation of cubic spinel structure. The lattice constant "a" increases from 8.3397Å for MgFeNiO 4 to 8.3855Å for ZnFeNiO 4 spinels. The increases in lattice parameters have been attributed to the replacement of small Mg 2+ ions (0.66 Å) with the Zn 2+ (0.74 Å) ions of a larger ionic radius. The IR spectra confirm the existence of two main absorption bands υ 1 and υ 2 in the frequency range of (400-1000 cm-1), arising due to the tetrahedral (A) and octahedral (B) stretching vibrations respectively. Values of both υ 1 and υ 2 decrease as Zn content increases. The scanning electron microscope (SEM) and transmission electron microscope (TEM) images showed aggregates of stacked grains. The normalized XRD intensities of the main (hkl) planes were used in the estimation of the Debye-Waller factor. Values of the Debye-Waller factors were estimated to be in the range (0.77-1.44A 2). The calculated and observed relative intensities and areas of the most related plains to cation distributions (i.e.: the (220), (311), (222), (400), (422), (511) and (440) plains) were obtained by normalizing with respect to the most intensive reflection from the (311) plane. An inverse relation between the ordering, Q and inversion, λ factors exists in these partially inverse spinels. Both Q and λ decrease as Zn content (x) increases in the sample. The cation distributions indicate that the sample, MgFeNiO 4 with x=0, λ=2/3 and maximum configurational entropy Sc(=15.876 J/mol, K) should represents the sample of the complete randomness of cation distributions in these spinels and can be written as (Mg 1/3 Fe 2/3)[Mg 2/3 Fe 1/3 Ni 3/3)O 4. In general the variation of the different structural parameters with Zn content lie on two different regions, the first region for x values (0.0-0.6) the "highly normal" and the second region for x values (0.6-1.0) the "highly inverse" type structure.

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Section: Debye-waller Factor (Dwf)mentioning

confidence: 99%

“…x Cr x O 4 [22][23][24][25] and MgFe 2-x Cr x O 4 [24][25][26][27] spinels, in which the values of the bands ν 1 and ν 2 shift to higher values (increase) with the Cr content. Figure 19-b shows details of the other absorption bands.…”

Section: The Ft-ir Analysismentioning

confidence: 99%

Effects of Zn Substitution on Structure Factors, Debye-Waller Factors and Related Structural Properties of the Mg1-xZnxFeNiO4 Spinels

Khalaf¹

2019

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“…Paper [8] presents results of crystallographic studies and Raman spectroscopy of ferrite of MgCr x Fe 2−x O 4 (0≤x≤1) system and works [9,10] have revealed crystal-chemical and magnetic properties of the MgCr x Fe 2-х O 4 system ferrites obtained by the ceramic technology from a mixture of oxides. Magnesium chromite with lattice parameter of 8.3347 Å and average particle size of 85-124 nm was synthesized from solutions of metallic nitrates in a stochiometric ratio by hydrothermal method at various pH, temperature and time values [11].…”

Section: Analysis Of the Published Data And Problem Statementmentioning

confidence: 99%

“…Electrical resistivity of nanoferrites of MgCr x Fe 2−x O 4 (0≤x≤1) system obtained by gel-citrate method was measured by authors of work [13]. However, no data on studies of magnetic microstructure by Mössbauer spectroscopy were given in papers [8][9][10][11][12][13].…”

Section: Analysis Of the Published Data And Problem Statementmentioning

confidence: 99%

Mössbauer studies of spinellides of Mg(FeXCr2-X)O4 system obtained by the hydroxide co-precipitation method

Luсas

Moklyak

Yaremiy

et al. 2017

EEJET

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“…In the form of powdery, thick or thin film ferrites have been prepared by conventional double sintering technique, a coprecipitation method, traditional ceramic method, a sol-gel method, high-temperature solid-state reaction method, etc. [9][10][11][12][13]. The main point to achieve highperformance ferrite synthesis depends on finding a specific technique to incline it giving the compositionally stoichiometric product.…”

Section: Introductionmentioning

confidence: 99%

The Effect of Al³⁺ Additive on the Structural, Optical, and Magnetic Properties of Al-Cd Ferrites Fabricated by Coprecipitation Method

2018

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In the present study, Al-Cd ferrites of nominal composition AlxCd1−xFe2O4 (x = 0-0.5) were prepared by coprecipitation method. The effect of Al +3 additive on the structural, optical, and magnetic properties of the as-prepared Al-Cd ferrites was investigated. Samples were characterized by X-ray diffraction, scanning electron microscopy, the Fourier transform infrared spectroscopy, UV spectroscopy and vibrating sample magnetometer techniques. The magnetic analysis indicated that all of the samples in different compositions showed ferromagnetic behavior. Along with the X-ray diffraction patterns, the formation of single-phase cubic spinel structure and the lattice parameter were identified in the range of 8.6492-8.6984 Å. Scanning electron microscopy measurements showed that the smallest ferrite nanoparticles were obtained when the stoichiometric composition factor (x) value was 0.4. As an additional characterization, the Fourier transform infrared spectra was investigated, and the characteristic absorption, bands belonging to ferrite nanoparticles were identical around 530 cm −1 and 430 cm −1. The tetrahedral and the octahedral complex formation was proved by the observation of higher frequency (ν1), and lower frequency (ν2) bands by Fourier transform infrared method, respectively. UV-Vis characterization performed for the determination of Eg values depending on changing Al concentration and found as 2.07-2.24 eV. From the magnetic measurements, all the Al-doped Cd ferrites exhibit S-shaped narrow hysteresis loops revealing soft ferromagnetic nature of the formed ferrites.

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Structural Rietveld refinement and vibrational study of MgCr x Fe 2−x O 4 spinel ferrites

Cited by 54 publications

References 30 publications

Effects of Zn Substitution on Structure Factors, Debye-Waller Factors and Related Structural Properties of the Mg<sub>1-x</sub>Zn<sub>x</sub>FeNiO<sub>4</sub> Spinels

Effects of Zn Substitution on Structure Factors, Debye-Waller Factors and Related Structural Properties of the Mg<sub>1-x</sub>Zn<sub>x</sub>FeNiO<sub>4</sub> Spinels

Mössbauer studies of spinellides of Mg(FeXCr2-X)O4 system obtained by the hydroxide co-precipitation method

The Effect of Al³⁺ Additive on the Structural, Optical, and Magnetic Properties of Al-Cd Ferrites Fabricated by Coprecipitation Method

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Structural Rietveld refinement and vibrational study of MgCr x Fe 2−x O 4 spinel ferrites

Cited by 54 publications

References 30 publications

Effects of Zn Substitution on Structure Factors, Debye-Waller Factors and Related Structural Properties of the Mg&lt;sub&gt;1-x&lt;/sub&gt;Zn&lt;sub&gt;x&lt;/sub&gt;FeNiO&lt;sub&gt;4&lt;/sub&gt; Spinels

Effects of Zn Substitution on Structure Factors, Debye-Waller Factors and Related Structural Properties of the Mg&lt;sub&gt;1-x&lt;/sub&gt;Zn&lt;sub&gt;x&lt;/sub&gt;FeNiO&lt;sub&gt;4&lt;/sub&gt; Spinels

Mössbauer studies of spinellides of Mg(FeXCr2-X)O4 system obtained by the hydroxide co-precipitation method

The Effect of Al3+ Additive on the Structural, Optical, and Magnetic Properties of Al-Cd Ferrites Fabricated by Coprecipitation Method

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Effects of Zn Substitution on Structure Factors, Debye-Waller Factors and Related Structural Properties of the Mg<sub>1-x</sub>Zn<sub>x</sub>FeNiO<sub>4</sub> Spinels

Effects of Zn Substitution on Structure Factors, Debye-Waller Factors and Related Structural Properties of the Mg<sub>1-x</sub>Zn<sub>x</sub>FeNiO<sub>4</sub> Spinels

The Effect of Al³⁺ Additive on the Structural, Optical, and Magnetic Properties of Al-Cd Ferrites Fabricated by Coprecipitation Method