Exploring Crystal Structure, Hyperfine Parameters, and Magnetocaloric Effect in Iron-Rich Intermetallic Alloy with ThMn₁₂-Type Structure: A Comprehensive Investigation Using Experimental and DFT Calculation

In this study, we give a thorough evaluation of the structural, magnetic, and magnetocaloric properties in iron-rich PrFe11Ti intermetallic alloy with ThMn12-type structure using a combination of experimental and theoretical analysis. X-ray diffraction coupled with Rietveld refinement was used to characterize the structure, which revealed a unique tetragonal crystal structure with I4/mmm space group. The 8i site was identified as the preferred site for the Ti atom. This finding was confirmed by various techniques, including XRD, DFT, and Mössbauer spectrometry. Magnetic properties were studied through intrinsic magnetic measurements and magnetocaloric effect analysis. Mössbauer spectroscopy was employed to probe the local magnetic environment and for further characterization of the material’s magnetic properties. The experimental results were complemented by theoretical calculations based on density functional theory (DFT). A promising magnetocaloric effect is observed, with a significant maximum magnetic entropy (−ΔSMmax = 2.5 J·kg−1·K−1) and a relative cooling power about 70 J·kg−1 under low magnetic field change μ0ΔH = 1.5 T. Overall, our results provide a deeper understanding of the structural and magnetic properties of the material under study and demonstrate the effectiveness of the combined experimental and theoretical approach in the investigation of complex materials. The insights gained from this study could have implications for the development of advanced magnetic materials with enhanced properties for potential magnetic applications

Impact of Annealing Temperature on the Physical Properties of the Lanthanum Deficiency Manganites

International audienceThe lanthanum deficiency manganites La0.8-x□xCa0.2MnO3 (x = 0, 0.1 and 0.2), where □ is a lanthanum vacancy, were prepared using the classic ceramic methods with different thermal treatments (1373 K and 973 K). The structural, magnetic, and magnetocaloric properties of these compounds were studied as a function of annealing temperature. It was noted that the annealing temperature did not affect the crystal structure of our samples (orthorhombic structure with Pnma space group). Nevertheless, a change in the variation of the unit cell volume V, the average bond length dMn–O, and the average bond angles θMn–O–Mn were observed. Magnetization versus temperature study has shown that all samples exhibited a magnetic transition from ferromagnetic (FM) to paramagnetic (PM) phase with increasing temperature. However, it can be clearly seen that the annealing at 973 K induced an increase of the magnetization. In addition, the magnetocaloric effect (MCE) as well as the relative cooling power (RCP) were estimated. As an important result, the values of MCE and RCP in our Lanthanum-deficiency manganites are reported to be near to those found in gadolinium, considered as magnetocaloric reference material

Unraveling the multi-featured magnetic behavior of Nd0.75Sr0.25CoO3 perovskite nanocrystals annealed at different temperatures

Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGPerovskite nanocrystals are gaining increased attention because of their magnetic, transport and catalytic properties, and particularly there is a renewable interest of cobalt perovskites for catalysis. Accordingly, the correct interpretation of their properties stemming from a particular configuration of the cations within this crystalline structure is compulsory. Herein, we report the synthesis of Nd0.75Sr0.25CoO3 nanocrystals using the citrate sol-gel method and annealed at different final temperatures (600 °C, 700 °C, 800 °C and 1150 °C). Their characterization was carried out combining transmission electron microscopy, X-ray diffraction, Raman spectroscopy and vibrating sample magnetometry, demonstrating their complementarity to get the whole picture of the multi-featured perovskite-based nanocrystal behavior.Xunta de Galicia | Ref. ED431C 2016-034Ministerio de Economía y Competitividad | Ref. CTM2017-84050-

Deciphering the Structural Characterization, Hirshfeld Surface Analysis, Raman Studies, and Temperature-Dependent Magnetodielectric Properties of BiMn2O5

We investigate the structural, Hirshfeld surface, magnetic, and magnetodielectric properties of BiMn2O5. The sample can be indexed with an orthorhombic phase associated with space group Pbam, with crystallographic parameters a = 7.54946 Å, b = 8.54962 Å and c = 5.753627 Å. The Hirshfeld surface analysis, associated with 2D fingerprint plots, was used to visualize and explore the significant intermolecular interactions in the crystal structure quantitatively. The Raman spectra, measured from 6 to 300 K in a frequency range between 250 and 750 cm−1, exhibit good agreement between the SHELL model calculations and the experimental measurement of the proximity of the phonon frequencies for our sample. Furthermore, magnetic measurements show that BiMn2O5 becomes antiferromagnetic below the Néel temperature (TN)—the temperature above which an antiferromagnetic material becomes paramagnetic (TN = 31 K). The relaxation at intermediate temperatures (200–300 K) can be attributed to the polar jump process at two charge transfer sites between the Mn3+ and Mn4+ ions, which, in combination with the special arrangement of the Mn3+/Mn4+ ions, is likely to produce the strong intrinsic magnetodielectric effect (MD) in the same temperature range

Deciphering the Structural Characterization, Hirshfeld Surface Analysis, Raman Studies, and Temperature-Dependent Magnetodielectric Properties of BiMn2O5

We investigate the structural, Hirshfeld surface, magnetic, and magnetodielectric properties of BiMn2O5. The sample can be indexed with an orthorhombic phase associated with space group Pbam, with crystallographic parameters a = 7.54946 Å, b = 8.54962 Å and c = 5.753627 Å. The Hirshfeld surface analysis, associated with 2D fingerprint plots, was used to visualize and explore the significant intermolecular interactions in the crystal structure quantitatively. The Raman spectra, measured from 6 to 300 K in a frequency range between 250 and 750 cm1, exhibit good agreement between the SHELL model calculations and the experimental measurement of the proximity of the phonon frequencies for our sample. Furthermore, magnetic measurements show that BiMn2O5 becomes antiferromagnetic below the Néel temperature (TN)—the temperature above which an antiferromagnetic material becomes paramagnetic (TN = 31 K). The relaxation at intermediate temperatures (200–300 K) can be attributed to the polar jump process at two charge transfer sites between the Mn3+ and Mn4+ ions, which, in combination with the special arrangement of the Mn3+/Mn4+ ions, is likely to produce the strong intrinsic magnetodielectric effect (MD) in the same temperature range

Tetragonal tungsten bronze/barium hexaferrite room-temperature multiferroic composite ceramics

The spontaneously formed multiferroic composite based on tetragonal tungsten bronze structure was successfully synthesized in the form of ceramics by the solid-state reaction. The crystallization of the ceramics in the tetragonal tungsten bronze structure Ba2SmFeNb4O15 and the presence of a secondary magnetic phase of barium hexaferrite BaFe12O19 were established by structural investigation. The hysteresis behavior describing the polarization as a function of an applied electric field and the high ferroelectric Curie temperature ≈ 417 K evidenced the room-temperature ferroelectric properties of the synthesized material. While the piezoelectric coefficients were determined to be around 1.3 pm/V, the microscopic polar domains of the composite ceramics were established by microelectromechanical study. The hysteresis loop of the magnetization versus magnetic field and the high magnetic transition temperature ≈ 590 K evidenced the ferromagnetic properties of the secondary phase and its presence at room temperature. Moreover, the spatial distribution of the magnetic domains was determined microscopically. In this study, not only the multiferroic properties of the Ba2SmFeNb4O15/BaFe12O19 composites have been studied and presented, but the distribution of the polar and magnetic properties was locally investigated as well

High electrical conductivity at room temperature of MnCo2O4 cobaltite spinel prepared by sol gel method

1118-C22B-190A | Ahmed Dhahriinfo:eu-repo/semantics/acceptedVersio

Effect of Ni-doping on structural, magnetic and magnetocaloric properties of La0.6Pr0.1Ba0.3Mn1−xNixO3 nanocrystalline manganites synthesized by Pechini sol–gel method

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Effect of Ni-doping on critical behavior of La0.6Pr0.1Ba0.3Mn1−xNixO3 nanocrystalline manganites

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Magnetic Refrigeration: Application to the Electron Doped Manganites

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