Structural Transition and Magnetic Properties of (Sr2-3xLa2xBax)FeMoO6

Ordered double perovskite oxides (Sr2-3xLa2xBax)FeMoO6 (0≤x≤0.3) have been investigated in this work. X-ray powder diffraction reveals that the crystal structure of the compounds changes from a tetragonal I4/m lattice to a cubic Fm 3m lattice around x=0.2. Though the nominal average size of the A site cation of (Sr2-3xLa2xBax)FeMoO6 is designed to be almost independent of x, the refinements of the crystal structure show that the lattice constants increase with x in both the tetragonal and the cubic phase regions due to electron doping. As the x increases, the degree of cationic ordering on the B site is decreased pronouncedly, while the Curie temperature of the compounds is nearly unchanged.

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Effect of Sm Doping on Magnetic Properties of Sr2FeMoO6

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.76 ◽

2010 ◽

Vol 663-665 ◽

pp. 76-79

Author(s):

Zhen Feng Xu ◽

Jun Liang ◽

Juan Pei ◽

Yan Yan Yin ◽

Chang Li

Keyword(s):

Crystal Structure ◽

Magnetic Properties ◽

Rare Earth ◽

Single Phase ◽

Steric Effect ◽

Magnetic Measurements ◽

Double Perovskite ◽

Rare Earth Ions ◽

X Ray ◽

Curie Temperature Tc

New electron doped double perovskite compound (Sr2-xSmx) FeMoO6 (0≤x≤0.25) has been synthesized by solid-state reaction. Crystal structure and magnetic properties of the compounds have been investigated by X-ray powder diffraction (XRD) and magnetic measurements. XRD revealed that all the compounds were of single phase and belonged to a I 4/m lattice. The degree of cationic ordering on the B site was decreased pronouncedly by the electron doping. Different from the results of La- and Nd-doped Sr2FeMoO6, Curie temperature (TC) of (Sr2-xSmx) FeMoO6 decreased first with the doping and then increased beyond x = 0.15, indicating that steric effect was enhanced as the radius of rare-earth ions decreased.

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Magnetic Property of Hole-Doped Double Perovskite Compound

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.464.50 ◽

2013 ◽

Vol 464 ◽

pp. 50-53

Author(s):

Suo Jia Yuan ◽

Qin Zhang ◽

Hai Bo Sun ◽

Hui Wang

Keyword(s):

Crystal Structure ◽

Magnetic Properties ◽

Doping Level ◽

Single Phase ◽

Magnetic Measurements ◽

Double Perovskite ◽

Cation Ordering ◽

High Doping Level ◽

Xrd Pattern ◽

X Ray

Crystal structure and magnetic properties of hole-doped double perovskite compounds (Sr, Na)2FeMoO6 have been investigated by means of X-ray powder diffraction (XRD) and magnetic measurements. XRD pattern indicates that all the samples are of single phase and belong to the space group I4/m. The degree of cation ordering in the Na-doped Sr2FeMoO6 compounds shows a non-monotonic variation with the doping level, increasing from x=0 to x=0.03 and decreasing slightly with further increase of the doping. However, the Curie temperature of the compound decreases at low doping level and increases at high doping level.

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Tunable magnetization steps in mixed valent ferromagnet Eu2CoMnO6

Scientific Reports ◽

10.1038/s41598-021-88950-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Nara Lee ◽

Jong Hyuk Kim ◽

Dong Gun Oh ◽

Hyun Jun Shin ◽

Hwan Young Choi ◽

...

Keyword(s):

Material Processing ◽

Magnetic Properties ◽

Single Crystals ◽

Magnetic State ◽

Hysteresis Loops ◽

Double Perovskite ◽

Processing Parameters ◽

Perovskite Oxides ◽

Efficient Approach ◽

Isothermal Magnetization

AbstractMagnetic properties can be manipulated to enhance certain functionalities by tuning different material processing parameters. Here, we present the controllable magnetization steps of hysteresis loops in double-perovskite single crystals of Eu2CoMnO6. Ferromagnetic order emerges below TC ≈ 122 K along the crystallographic c axis. The difficulty in altering Co2+ and Mn4+ ions naturally induces additional antiferromagnetic clusters in this system. Annealing the crystals in different gas environments modifies the mixed magnetic state, and results in the retardation (after O2-annealing) and bifurcation (after Ar-annealing) of the magnetization steps of isothermal magnetization. This remarkable variation offers an efficient approach for improving the magnetic properties of double-perovskite oxides.

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Crystal Structure Refinements of Four Monazite Samples from Different Localities

Minerals ◽

10.3390/min10111028 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1028 ◽

Cited By ~ 1

Author(s):

M. Mashrur Zaman ◽

Sytle M. Antao

Keyword(s):

Crystal Structure ◽

Electron Probe ◽

Unit Cell Volume ◽

Unit Cell ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

X Ray ◽

Cell Parameters ◽

Large Unit Cell ◽

A Site

This study investigates the crystal chemistry of monazite (APO4, where A = Lanthanides = Ln, as well as Y, Th, U, Ca, and Pb) based on four samples from different localities using single-crystal X-ray diffraction and electron-probe microanalysis. The crystal structure of all four samples are well refined, as indicated by their refinement statistics. Relatively large unit-cell parameters (a = 6.7640(5), b = 6.9850(4), c = 6.4500(3) Å, β = 103.584(2)°, and V = 296.22(3) Å3) are obtained for a detrital monazite-Ce from Cox’s Bazar, Bangladesh. Sm-rich monazite from Gunnison County, Colorado, USA, has smaller unit-cell parameters (a = 6.7010(4), b = 6.9080(4), c = 6.4300(4) Å, β = 103.817(3)°, and V = 289.04(3) Å3). The a, b, and c unit-cell parameters vary linearly with the unit-cell volume, V. The change in the a parameter is large (0.2 Å) and is related to the type of cations occupying the A site. The average <A-O> distances vary linearly with V, whereas the average <P-O> distances are nearly constant because the PO4 group is a rigid tetrahedron.

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ANNEALING EFFECT ON THE INDUCED MAGNETISM OF PLATINUM IN FePt NANOPARTICLES

Modern Physics Letters B ◽

10.1142/s0217984907013894 ◽

2007 ◽

Vol 21 (18) ◽

pp. 1189-1196 ◽

Cited By ~ 4

Author(s):

F. WILHELM ◽

A. ROGALEV ◽

P. POULOPOULOS ◽

M. ANGELAKERIS ◽

J. TSIAOUSSIS ◽

...

Keyword(s):

Magnetic Properties ◽

Magnetic Circular Dichroism ◽

Annealing Effect ◽

Fept Nanoparticles ◽

X Ray ◽

Remanence Ratio ◽

Structural And Magnetic Properties ◽

Coercivity Field ◽

Average Size ◽

Magnetic Circular Dichroism Spectra

Effect of annealing on structural and magnetic properties of non-equatomic chemically synthesized FePt nanoparticles with an average size of 3.2 nm diameter is reported. Annealing of the particles at 700°C resulted in the increase of particles size and the enhancement of total magnetization and coercivity, the latter could be attributed to a transformation from disordered to ordered crystallographic phase. Although the system is far from optimum "equatomic" stoichiometry, coercivity field of 1.1 kOe was obtained at 10 K together with remanence ratio of 0.55. X-ray magnetic circular dichroism spectra recorded at the Pt L 2,3 edges on annealed samples revealed the enhancement of magnetic moment induced on Pt atom.

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Synthesis, Crystal Structure and Magnetic Behaviour of Dimeric and Polymeric Gadolinium Trifluoroacetate Complexes

Zeitschrift für Naturforschung B ◽

10.1515/znb-2006-0608 ◽

2006 ◽

Vol 61 (6) ◽

pp. 699-707 ◽

Cited By ~ 8

Author(s):

Daniela John ◽

Alexander Rohde ◽

Werner Urland

Keyword(s):

Crystal Structure ◽

Magnetic Behaviour ◽

Magnetic Data ◽

Space Group ◽

X Ray ◽

Lattice Constants ◽

Temperature Range ◽

X Ray Crystallography ◽

Carboxylate Groups

The gadolinium(III) trifluoroacetates ((CH3)2NH2)[Gd(CF3COO)4] (1), ((CH3)3NH)[Gd(CF3 COO)4(H2O)] (2), Gd(CF3COO)3(H2O)3 (3) as well as Gd2(CF3COO)6(H2O)2(phen)3 · C2H5OH (4) (phen = 1,10-phenanthroline) were synthesized and structurally characterized by X-ray crystallography. These compounds crystallize in the space group P1̅ (No. 2, Z = 2) (1, 2 and 4) and P 21/c (No. 14, Z = 4) (3), respectively, with the following lattice constants 1: a = 884.9(2), b = 1024.9(2), c = 1173.1(2) pm, α = 105.77(2), β = 99.51(2), γ = 107.93(2)°; 2: a = 965.1(1), b = 1028.6(1), c = 1271.3(2) pm, α = 111.83(2), β = 111.33(2), γ = 90.44(2)°; 3: a = 919.6(2), b = 1890.6(4), c = 978.7(2) pm, β = 113.94(2)°; 4: a = 1286.7(8), b = 1639.3(8), c = 1712.2(9) pm, α = 62.57(6), β = 84.13(5), γ = 68.28(5)°. The compounds consist of Gd3+ ions which are bridged by carboxylate groups either to chains (1 and 2) or to dimers (3 and 4). In addition to the Gd3+ dimers, compound (4) also contains monomeric Gd3+ units. The magnetic behaviour of 2 and 3 was investigated in a temperature range of 1.77 to 300 K. The magnetic data for these compounds indicate weak antiferromagnetic interactions

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ChemInform Abstract: High-Pressure Synthesis, Crystal Structures, and Magnetic Properties of 5d Double-Perovskite Oxides Ca2MgOsO6and Sr2MgOsO6.

ChemInform ◽

10.1002/chin.201524014 ◽

2015 ◽

Vol 46 (24) ◽

pp. no-no

Author(s):

Yahua Yuan ◽

Hai L. Feng ◽

Madhav Prasad Ghimire ◽

Yoshitaka Matsushita ◽

Yoshihiro Tsujimoto ◽

...

Keyword(s):

High Pressure ◽

Magnetic Properties ◽

Crystal Structures ◽

Double Perovskite ◽

Perovskite Oxides ◽

High Pressure Synthesis ◽

Pressure Synthesis

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Zur Kenntnis eines Barium-Oxoniobat-Tellurats: Ba2Nb2TeO10 / On a Barium-Oxoniobate-Tellurate: Ba2Nb2TeO10

Zeitschrift für Naturforschung B ◽

10.1515/znb-1996-1006 ◽

1996 ◽

Vol 51 (10) ◽

pp. 1407-1410 ◽

Cited By ~ 5

Author(s):

B. Wedel ◽

Hk. Müller-Buschbaum

Keyword(s):

Crystal Structure ◽

Solid State ◽

Single Crystals ◽

Solid State Reactions ◽

Orthorhombic Symmetry ◽

X Ray ◽

Lattice Constants ◽

Group D ◽

Symmetry Space ◽

Symmetry Space Group

Single crystals of Ba2Nb2TeO10) have been prepared by solid state reactions in air. X-ray investigations led to orthorhombic symmetry, space group D152h-Pbca, a = 7.242(4), b = 12.433(3), c = 9.932(3) Å. Z = 4. Nb5+ and Te6+ show octahedral coordination by O2- . The crystal structure is characterized by planes of edge- and corner-sharing NbO6- and TeO6octahedra. It is shown that in spite of nearly identical lattice constants of Ba2Nb2TeO10 with compounds of the composition M0,5BaNbTe2O9 the so far unknown crystals of these substances may not be derived from the Ba2Nb2TeO10 type.

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