•PrCo2 single crystals grown with a Boron Nitride (BN) crucible.•Reaction between the Pr-Co liquid melt and alumina crucible.•The experimentally observed saturation moment matches theoretically ...calculated value.
Single crystals of PrCo2 have been grown from flux starting from Pr0.44Co0.56 that was synthesized by arc melting of stoichiometric mixtures of the elements. The Pr0.44Co0.56 ingot was loaded in a Boron Nitride (BN) crucible and sealed inside a quartz tube under vacuum. The quartz ampoule was heated to 1203 K, and then slowly cooled down to 923 K at a rate of 2 K/h. The obtained crystals have octahedral shapes and are of cubic C15 Laves phase structure confirmed by room temperature powder and single-crystal X-ray diffraction measurements. Magnetic susceptibility data show the Curie temperature TC = 46.7 K. The experimental value of saturation magnetization Ms = 3.2 μB/f.u is consistent with our theoretical calculations.
Large magnetoresistance effects were observed in Ni50Mn50-xSnx Heusler alloys for concentrations 13x16. The effects occur at the respective martensitic transition temperatures (TM), which can be ...tuned in temperature through variations in Sn concentration. The largest observed values of the magnetoresistance (Deltarho/rhoo) were -42% for x=14 at Tapprox 250K, and -23% above room temperature (Tapprox 320K) for the sample with x=13, where the magnetic field change was DeltaH=5T. Magnetization and X-ray diffraction measurements indicate that the origin of the observed magnetoresistance is a magnetically induced magnetostructural transition from a complex 10M modulated orthorhombic phase containing some antiferromagnetic coupling to a ferromagnetic cubic L21 structure.
Unique from other rare earth dialuminides, PrAl(2) undergoes a cubic to tetragonal distortion below T = 30 K in a zero magnetic field, but the system recovers its cubic symmetry upon the application ...of an external magnetic field of 10 kOe via a lifting of the 4f crystal field splitting. The nuclear Schottky specific heat in PrAl(2) is anomalously high compared to that of pure Pr metal. First principles calculations reveal that the 4f crystal field splitting in the tetragonally distorted phase of PrAl(2) underpins the observed unusual low temperature phenomena.
Crystallographic, magnetic, electrical transport and thermodynamic properties of pseudo-binary Nd7Ni2Pd compound have been studied using temperature-dependent x-ray powder diffraction and physical ...property measurements. Compared to the ferromagnetic parent Nd7Pd3, the ground state of Nd7Ni2Pd is antiferromagnetic, and it exhibits strong metamagnetism. The measurements indicate two antiferromagnetic transitions in fields less than 8 kOe: a second-order paramagnetic to antiferromagnetic at TN2 = 29 K and a weak first-order antiferromagnetic to antiferromagnetic transition at TN1 = 24.5 K. The compound becomes ferromagnetic in fields of 8 kOe and higher with TC = 30 K. Temperature dependence of lattice parameters is anomalous, most prominently in the basal plane at ∼30 K; however, there is no detectable structural distortion or clear volume discontinuity around 25 K, suggesting a significant weakening of the first-order transition when compared to the binary Nd7Pd3.
We report on the magnetic behaviour of Nd5Ge3 by investigating through magnetization, neutron diffraction and muon spin relaxation measurements. Temperature dependent-magnetization, muon ...depolarization rate (λ), initial asymmetry (A0) and the stretched exponent (β) show a clear anomaly at the Néel temperature TN ∼ 54 K. However, the short-range correlated ferromagnetic interactions below TN are inferred from the diffuse scattering mechanism as revealed by zero-field neutron diffraction data. Narrow first order phase transition is due to the competing interaction of a high temperature weak-antiferromagnetic and low temperature glassy states. Magnetic field-induced reentrant spin glass state from a magnetic glass state is observed, before it transforms to a ferromagnetic state.
Our 151Eu Mössbauer investigation of Eu2In and Eu2Sn shows that the europium in both materials is fully divalent. We confirm the distinct thermodynamic orders of the magnetic transitions and reveal a ...remarkable difference between the magnetic environments of the europium atoms in the two compounds. Possible structural and electronic origins for these differences are discussed using DFT calculations.
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