Antiferromagnetic behavior in Y–Ba–(Cu1−xScx)–O

1989 ◽  
Vol 4 (3) ◽  
pp. 467-469 ◽  
Author(s):  
A. Chakraborty ◽  
X. D. Chen ◽  
F. Zuo ◽  
B. R. Patton ◽  
J. R. Gaines ◽  
...  
Keyword(s):  
Magnetic Susceptibility ◽  
Composition Range ◽  
Second Phase ◽  
Superconducting Transition ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Susceptibility Study ◽  
New Phase ◽  
Antiferromagnetic Behavior

We report the results on x-ray diffraction and magnetic susceptibility study of Y–Ba–(Cu1−xScx)–O. The materials were prepared in a stoichiometry corresponding to Y1Ba2(Cu1−xScx)3O7. Although x-ray analysis reveals the increasing presence of a subtle second phase with increasing Sc content, the superconducting transition temperature and resistivity did not change substantially in the composition range 0.0  x ≤ 0.15. In contrast, the magnetic susceptibility studies showed dramatic changes. Although Sc3+ has no spin by itself, an enhanced paramagnetic Curie susceptibility was observed above Tc with a moment of 1.5 μB per Sc. At 16 K a sharp cusp is observed in the temperature dependent susceptibility corresponding to the onset of a three-dimensionally ordered antiferromagnetic state. These results are discussed in terms of an additional previously unreported phase of Y–Ba–(Cu–Sc)–O that has an antiferromagnetic Néel temperature of 16 K. For composition of x = 1.0, a new phase is formed which is nonmagnetic.

Ternary Antimonides RE4T7Sb6 (RE=Gd–Lu; T =Ru, Rh) with Cubic U4Re7Si6-type Structure

2013 ◽  
Vol 68 (9) ◽  
pp. 971-978 ◽  
Author(s):  
Inga Schellenberg ◽  
Ute Ch. Rodewald ◽  
Christian Schwickert ◽  
Matthias Eul ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Susceptibility ◽  
Single Crystal ◽  
Magnetic Moment ◽  
Induction Furnace ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Antiferromagnetic Ordering ◽  
Arc Melting ◽  
Intermediate Valent

The ternary antimonides RE4T7Sb6 (RE=Gd-Lu; T =Ru, Rh) have been synthesized from the elements by arc-melting and subsequent annealing in an induction furnace. The samples have been characterized by powder X-ray diffraction. Four structures were refined on the basis of single-crystal X-ray diffractometer data: U4Re7Si6 type, space group Im3m with a=862.9(2) pm, wR2=0.0296, 163 F2 values for Er4Ru7Sb6; a=864.1(1) pm, wR2=0.1423, 153 F2 values for Yb4Ru7Sb6; a=872.0(2) pm, wR2=0.0427, 172 F2 values for Tb4Rh7Sb6; and a=868.0(2) pm, wR2=0.0529, 154 F2 values for Er4Rh7Sb6, with 10 variables per refinement. The structures have T1@Sb6 octahedra and slightly distorted RE@T26Sb6 cuboctahedra as building units. The distorted cuboctahedra are condensed via all trapezoidal faces, and this network leaves octahedral voids for the T1 atoms. The ruthenium-based series of compounds was studied by temperature-dependent magnetic susceptibility measurements. Lu4Ru7Sb6 is Pauli-paramagnetic. The antimonides RE4Ru7Sb6 with RE=Dy, Ho, Er, and Tm show Curie-Weiss paramagnetism. Antiferromagnetic ordering occurs at 10.0(5), 5.1(5) and 4.0(5) K for Dy4Ru7Sb6, Ho4Ru7Sb6 and Er4Ru7Sb6, respectively, while Tm4Ru7Sb6 remains paramagnetic. Yb4Ru7Sb6 is an intermediate-valent compound with a reduced magnetic moment of 3.71(1) μB per Yb as compared to 4.54 μB for a free Yb3+ ion

GdCuMg with ZrNiAl-type structure – an 82.2 K ferromagnet

2017 ◽  
Vol 72 (7) ◽  
pp. 511-515 ◽  
Author(s):  
Sebastian Stein ◽  
Lukas Heletta ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Susceptibility ◽  
Single Crystal ◽  
Magnetic Moment ◽  
Type Structure ◽  
Induction Melting ◽  
X Ray Diffraction ◽  
Muffle Furnace ◽  
Temperature Dependent ◽  
X Ray ◽  
Experimental Magnetic Moment

AbstractGdCuMg has been synthesized by induction-melting of the elements in a sealed niobium ampoule followed by annealing in a muffle furnace. The sample was studied by powder and single crystal X-ray diffraction: ZrNiAl type, P6̅2m (a=749.2(4), c=403.3(1) pm), wR2=0.0242, 315 F2 values and 15 variables. Temperature dependent magnetic susceptibility measurements have revealed an experimental magnetic moment of 8.54(1) μB per Gd atom. GdCuMg orders ferromagnetically below TC=82.2(5) K and based on the magnetization isotherms it can be classified as a soft ferromagnet.

scholarly journals X-Ray Powder Diffraction Study on the MgB2 Superconductor Reacted with Nano-SiC: The Effects of Sintering Temperature

2010 ◽  
Vol 173 ◽  
pp. 78-83
Author(s):  
Kwee Yong Tan ◽  
Tan Kim Lee ◽  
Lim Kean Pah ◽  
Shaari Abdul Halim ◽  
Tan Kar Ban ◽  
...  
Keyword(s):  
Phase Formation ◽  
Sintering Temperature ◽  
Lattice Parameter ◽  
Primary Phase ◽  
Superconducting Transition ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Higher Temperature ◽  
Addition Level

SiC added MgB2 polycrystalline samples were synthesized at low (650°C) and high (850°C) temperatures in order to study the sintering effect on the phase formation and superconducting properties. The MgB2 bulks with additions of 0wt%, 1wt%, 3wt% and 5wt% SiC were studied with powder X-ray diffraction technique. We observed that MgB2 remained as the primary phase for both sintering temperatures in all samples with the presence of MgO and Mg2Si as the main impurities. Some diffraction peaks associated with unreacted SiC is also noticeable. The relative intensity of the Mg2Si peaks was found to decrease in samples sintered at higher temperature. Temperature dependent magnetic moment measurements showed that the superconducting transition temperature, Tc decreases as the SiC addition level increases while lower sintering temperature degrades Tc to a greater extent. The changes in the physical properties is discussed based on the results of phase formation, full width half maximum (FWHM), lattice parameter and crystallite size.

Synthesis, reactivity and property of 5,15-dithiaporphyrin copper(II) complex

2014 ◽  
Vol 18 (08n09) ◽  
pp. 675-678 ◽  
Author(s):  
Naruhiko Wachi ◽  
Takeshi Kondo ◽  
Satoru Ito ◽  
Satoru Hiroto ◽  
Ji-Young Shin ◽  
...  
Keyword(s):  
Magnetic Susceptibility ◽  
Solid State ◽  
Sulfur Atom ◽  
Good Yield ◽  
Axial Ligand ◽  
Antiferromagnetic Interaction ◽  
Free Base ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray

Preparation of 5,15-dithiaporphyrin copper(II) complex was carried out by treatment of 5,15-dithiaporphyrin free-base with copper(II) acetate. X-ray diffraction analysis elucidated its dimeric structure in the solid state, in which the meso-sulfur atom served as an axial ligand to each pentacoordinated Cu ( II ) center. Temperature dependent magnetic susceptibility of the complex was measured to reveal the weak antiferromagnetic interaction between two Cu ( II ) centers in the solid state. 5,15-dithiaporphyrin Cu ( II ) complex was converted into 10-thiacorrole Cu ( II ) complex in good yield upon heating with triphenylphosphine in refluxing toluene.

Magnesium-rich Intermetallics RE3RuMg7 (RE=Y, Nd, Dy, Ho) – Rows of Condensed Ru@RE6/2 Octahedra in Magnesium Matrices

2013 ◽  
Vol 68 (12) ◽  
pp. 1273-1278 ◽  
Author(s):  
Marcel Kersting ◽  
Ute Ch. Rodewald ◽  
Christian Schwickert ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Susceptibility ◽  
Magnetic Moment ◽  
Small Degree ◽  
Intermetallic Phases ◽  
Metamagnetic Transition ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Antiferromagnetic Ordering ◽  
Experimental Magnetic Moment

The magnesium-rich intermetallic phases RE3RuMg7 (RE=Y, Nd, Dy, Ho) have been synthesized from the elements in sealed niobium ampoules and subsequently characterized by powder X-ray diffraction. The structure of the dysprosium compound was refined on the basis of single-crystal X-ray diffractometer data: Ti6Sn5 type, P63=mmc, a=1019.1(2), c=606.76(9) pm, wR2=0.0159, 439 F2 values, 19 variables. The Mg3 site shows a small degree of Mg3=Dy mixing, leading to the composition Dy3:03RuMg6:97 for the investigated crystal. The striking structural motifs in the Dy3RuMg7 structure are rows of face-sharing Ru@Dy6 octahedra and corner-sharing Mg2@Mg8Dy4 icosahedra. The rows of octahedra form a hexagonal rod-packing, and each rod is enrolled by six rows of the condensed icosahedra. Temperature-dependent magnetic susceptibility measurements of Dy3RuMg7 show Curie-Weiss behavior with an experimental magnetic moment of 10.66(1) µB per Dy atom. Antiferromagnetic ordering is detected at TN =27.5(5) K. The 5 K isotherm shows a metamagnetic transition at a critical field of HC =40 kOe

Deposition of Superconducting Thin Films of Magnesium Di-Boride on Various Substrates by Electroless Plating Process

2010 ◽  
Vol 654-656 ◽  
pp. 1840-1843
Author(s):  
Susil K. Putatunda ◽  
Khurpa S. Vijayaragavan ◽  
Gavin Lawes
Keyword(s):  
Thin Films ◽  
Electroless Plating ◽  
Magnesium Diboride ◽  
Superconducting Thin Films ◽  
Superconducting Transition ◽  
Superconducting Properties ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Gold Silver

Superconducting thin films of magnesium diboride (MgB2) has been synthesized on various substrates such as gold, silver, copper and silicon using a novel electroless plating technique. The microstructures and the superconducting properties of these films have been characterized using X-ray diffraction, scanning electron microscopy and temperature dependent magnetometry. X-ray diffraction measurements confirm that the films are crystalline magnesium diboride with some impurity phases. Clear evidence for a superconducting transition in the magnetization measurements was observed.

Effect of Yttrium Addition on Microstructure and Hardness of Cast EV31A Magnesium Alloy

2017 ◽  
Vol 740 ◽  
pp. 81-85
Author(s):  
Rosli Ahmad ◽  
Ashraf M.M. Elaswad ◽  
M.B.A. Asmael ◽  
N.R. Shahizan
Keyword(s):  
Rare Earth ◽  
Magnesium Alloy ◽  
Ternary Phase ◽  
Volume Fraction ◽  
Base Alloy ◽  
Second Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Yttrium Addition ◽  
New Phase

The effect of the rare earth (RE) element Y on the microstructure and hardness of (Mg–0.5Zn–0.5Zr–2.8Nd –1.5Gd) wt% Mg alloy investigated. 1 wt. % Y was added and compared with the base alloy. The microstructure results show the refinement of the grain by the addition of Y and the grains became smaller about 31.8 % and the volume fraction was increases 11.1% %, which led to the increment of hardness from 48.33 HV (as-cast EV31A) to 53.71 HV (as-cast EV31A +1 Y). Energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) results showed that the base alloy mainly contained α-Mg matrix and Mg-(Nd, Gd) as a second phase crystallized along the grain boundaries and addition of (Y) yttrium resulted in the formation of the new phase, Mg-Zn-Y-phase was found as a new ternary phase, where Y combined with the original second phase.

INVESTIGATION OF SUPERCONDUCTIVITY IN Y–Sr–Cu–O

1990 ◽  
Vol 04 (03) ◽  
pp. 195-199 ◽  
Author(s):  
R. SURYANARAYANAN ◽  
S. B. BALIGA ◽  
A. L. JAIN ◽  
O. GOROCHOV
Keyword(s):  
Magnetic Susceptibility ◽  
Nominal Composition ◽  
Ferromagnetic Transition ◽  
Superconducting Transition ◽  
X Ray Diffraction ◽  
X Ray ◽  
Higher Temperature

Preparation, X-ray diffraction (XRD), resistivity (ρ) and magnetic susceptibility (χ) of YSrCuO y (nominal composition) synthesized at 1200°C are reported. XRD data indicate more than one phase. Zero resistivity is observed at 72 K. The field cooled χ indicates a superconducting transition at 68 K and also an anti-ferromagnetic transition at 15 K which could be due to Y 2 Cu 2 O 5. These data confirm the earlier observations of Wu et al.5 who have, however, observed a higher T c at 85 K which could be due to a higher temperature used for synthesis.

From REZnSn to REZnSnH1:5 (RE = Pr, Nd) – Inducing Ferromagnetism through Hydrogenation

2013 ◽  
Vol 68 (11) ◽  
pp. 1191-1197 ◽  
Author(s):  
Bastian Reker ◽  
Bernard Chevalier ◽  
Oliver Niehaus ◽  
Ute Ch. Rodewald ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Susceptibility ◽  
Single Crystal ◽  
Magnetic Moments ◽  
Magnetic Ordering ◽  
Induction Melting ◽  
Stacking Sequence ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Free Ion

The ternary stannides PrZnSn and NdZnSn were synthesized by induction-melting of the elements in sealed tantalum tubes. They were characterized by powder and single-crystal X-ray diffraction: YPtAs-type structure, P63=mmc, a = 455:4(1) and c = 1650:3(2) pm, wR2=0.0266, 297 F2 for PrZnSn and a = 453:7(1) and c = 1637:0(4) pm, wR2=0.1558, 234 F2 for NdZnSn with 12 variables per refinement. PrZnSn and NdZnSn are AlB2 superstructures with slightly puckered and ordered [Zn3Sn3] hexagons in AA´BB´ stacking sequence along the crystallographic c axis. Hydrogenation results in the new hexagonal hydrides PrZnSnH1:5 (a = 447:98(8) and c = 1707:5(5) pm) and NdZnSnH1:5 (a = 448:28(8) and c = 1689:8(2) pm). Filling of RE3Zn tetrahedra by hydrogen leads to anisotropic changes of the lattice parameters and a drastic flattening of the [Zn3Sn3] layers. Temperature-dependent magnetic susceptibility measurements show Curie-Weiss behavior for PrZnSn and NdZnSn with experimental magnetic moments close to the free-ion values of RE3+. Magnetic ordering is detected at 4.7 (PrZnSn) and 6:5 K (NdZnSn). Hydrogenation induces ferromagnetism with increased ordering temperatures of 12.0 (PrZnSnH1:5) and 14:5 K (NdZnSnH1:5).

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