scholarly journals A Variety of Magnetism in CuMpt6 (M=3d Transition Metals) Ternary Alloys

1970 ◽  
Vol 32 (2) ◽  
Author(s):  
AK Das ◽  
AKM Zakaria ◽  
I Kamal
Keyword(s):  
Spin Glass ◽  
Quantum Interference ◽  
Magnetic Moments ◽  
Magnetic Behavior ◽  
Ternary Alloys ◽  
Ferromagnetic Behavior ◽  
Ferromagnetic Interaction ◽  
Glass Type ◽  
Academy Of Sciences ◽  
Curie Temperatures

The magnetic properties of polycrystalline CuMPt6 (M= Ti, V, Cr, Mn, Fe, Co and Ni) ternary alloys were studied by Superconducting Quantum Interference Device (SQUID) over the temperature range 4-300 K. Magnetization measurements revealed that the compounds containing M=Ti, V and Ni are paramagnetic. A spin glass type magnetic behavior appeared in the compounds with M= Cr and Mn in their annealed state and the corresponding temperatures for freezing the magnetic moments were Tg= 15 and 40 K, respectively. Positive values of the paramagnetic Curie temperature (Q) indicated that the ferromagnetic interaction is dominant in these spin-glass compounds. The compounds with M= Fe and Co showed ferromagnetic behavior having Curie temperatures (TC) = 230, and 190 K, respectively. Hysteresis study showed that the alloy with M=Co was magnetically softer than that with M=Fe. Keywords: CuMPt6 ternary alloys, Magnetic behavior, Effective magnetic moments (Peff), Spin glass type. doi: 10.3329/jbas.v32i2.2428 Journal of Bangladesh Academy of Sciences Vol.32(2) 2008 218-225

MAGNETIC BEHAVIOR OF U(TxAl1-x)2 COMPOUNDS (T=Co, Ni, Mn)

2006 ◽  
Vol 20 (26) ◽  
pp. 1677-1683
Author(s):  
P. LUCACI ◽  
E. CULEA
Keyword(s):  
Magnetic Fields ◽  
Magnetic Measurements ◽  
Magnetic Moments ◽  
Magnetic Behavior ◽  
Absolute Magnitude ◽  
Structural Data ◽  
Spin Fluctuations ◽  
Magnetic Parameters ◽  
Uranium Ion ◽  
Curie Temperatures

Magnetic behavior and structural data of the U(T x Al 1-x)2 compounds, where T = Co, Ni and Mn , were reported. Magnetic measurements were performed in the temperature range 4.2–800 K and magnetic fields up to 7 T. The gradual replacement of Al by Co , Ni and Mn ions leads to the decrease of the effective magnetic moments per uranium ion, and of the paramagnetic Curie temperatures in absolute magnitude. This composition evolution of the two magnetic parameters of the U(T x Al 1-x)2 compounds suggests a gradual suppression of the spin fluctuations with replacing the Al ions by T ions.

scholarly journals Zum paramagnetischen Verhalten von Palladium/Silber/Eisen- Legierungen/ On the Paramagnetic Behaviour of Palladium-Silver-Iron Alloys

1975 ◽  
Vol 30 (5) ◽  
pp. 645-655
Author(s):  
Peter Brill
Keyword(s):  
Electron Concentration ◽  
Magnetic Moments ◽  
Alloy Series ◽  
Band Filling ◽  
Paramagnetic Behaviour ◽  
Field Coefficient ◽  
Saturation Moment ◽  
Molecular Field Coefficient ◽  
The Moment ◽  
Curie Temperatures

Abstract The paramagnetic susceptibility of four PdAgFe alloy series containing 1, 3, 5 and 7 at. % Fe have been measured between 20° and 150 °C. On the basis of a band filling model the local moment contribution to the susceptibility has been evaluated according to a Curie -Weiss law. Assuming that the iron atoms donate 3 electrons and the silver atoms 1 electron to the Pd 4d band, the effective magnetic moments and the paramagnetic Curie temperatures of all the alloys can be represented by a single curve against the electron concentration. The effective magnetic moment is consistent with an Fe moment of 5.92 μB localized on the iron sites and a Pd moment varying with electron concentration and temperature. The same turns out to be true for the ferromagnetic region where the saturation moment, obtained on PdFe alloys and a PdAgFe alloy by different authors, is considered to arise from a localized Fe moment of 5 μB and a concentration dependent Pd moment. The molecular field coefficient for the interaction between the Fe moments and the Pd 4d electrons is found to be 850 mol/cm3 at 385 K and 1200 mol/cm3 at 0 K. Finally, the iron moment suggested in this work is contrasted with the moment derived from neutron diffraction measurements.

scholarly journals Exchange Bias in a Layered Metal–Organic Topological Spin Glass

2020 ◽  
Author(s):  
Ryan Murphy ◽  
Lucy Darago ◽  
Michael Ziebel ◽  
Elizabeth A. Peterson ◽  
Edmond W. Zaia ◽  
...  
Keyword(s):  
Spin Glass ◽  
Exchange Bias ◽  
Low Temperatures ◽  
2D Materials ◽  
Magnetic Behavior ◽  
Spin Frustration ◽  
Geometrically Frustrated ◽  
Spin Freezing ◽  
Metal Organic ◽  
Phase Chemistry

<p><b>The discovery of conductive and magnetic two-dimensional (2D) materials is critical for the development of next generation spintronics devices. Coordination chemistry in particular represents a highly versatile, though underutilized, route toward the synthesis of such materials with designer lattices. Here, we report the synthesis of a conductive, layered 2D metal–organic kagome lattice, Mn<sub>3</sub>(C<sub>6</sub>S<sub>6</sub>), using mild solution-phase chemistry. Strong geometric<i> </i>spin frustration in this system mediates spin freezing at low temperatures, which results in glassy magnetic behavior consistent with a geometrically frustrated (topological) spin glass. Notably, the material exhibits a large exchange bias of 1625 Oe, providing the first example of exchange bias in a coordination solid or a topological spin glass. More generally, these results demonstrate the potential utility of geometrically frustrated lattices in the design of new nanoscale spintronic materials.</b></p>

Synthesis and Structural Characterization of Ferromagnetic Au/Co Nanoparticles

2014 ◽  
Vol 1708 ◽  
Author(s):  
Nabraj Bhattarai ◽  
Subarna Khanal ◽  
Daniel Bahena ◽  
Robert L. Whetten ◽  
Miguel Jose-Yacaman
Keyword(s):  
Quantum Interference ◽  
Magnetic Measurements ◽  
Ferromagnetic Behavior ◽  
Contrast Imaging ◽  
Uniform Size ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Co Nanoparticles ◽  
Z Contrast

ABSTRACTThe synthesis of bimetallic magnetic nanoparticles is very challenging because of the agglomeration and non-uniform size. In this paper, we present the synthesis of monodispersed 3-5 nm sized thiolated bimetallic alloyed Au/Co nanoparticles with decahedral and icosahedral shape, their characterization using Cs-corrected scanning transmission electron microscopy (STEM) and magnetic measurements using superconducting quantum interference device (SQUID) magnetometer. The Z-contrast imaging and energy dispersive X-ray spectroscopy (EDS) mapping showed an inhomogeneous alloying with minor segregation between Au and Co at nanoscale and the SQUID measurement exhibited the ferromagnetic behavior.

Magnetic Properties of Intercalated Zinc Hexacyanoferrate (II)

2010 ◽  
Vol 168-169 ◽  
pp. 169-172
Author(s):  
Tatiana A. Denisova ◽  
Lidia G. Maksimova ◽  
Dina G. Kellerman ◽  
M.A. Melkozerova ◽  
Elena V. Zabolotskaya ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Molecular Mechanism ◽  
Magnetic Moments ◽  
Magnetic Behavior ◽  
Channel Structure ◽  
Nickel Ions ◽  
Behavior Study ◽  
Zinc Hexacyanoferrate

The results of magnetic behavior study of nickel ions, which were introduced into Zn2Fe(CN)6∙5.5H2O with channel structure, are presented. It was shown that nickel cations replace a part of Zn2+ ions or locate in the channels of lattice via the molecular mechanism sorption. It is shown that the magnetic moments μNi of the sorption products strongly depend on the content of Ni2+ ions. The values of μNi of the samples with Ni/Fe(CN)6=2.26 and 2.86 are great ~ 3.9 and 4.4 μB respectively and close to the value typical of free Ni2+ ions μ =4.47μB.

The Effect of Partial Substitution of Non-Magnetic Impurity Zn on the Magnetic Moments of Eu1.88Ce0.12Cu1-yZnyO4+α-δ

2021 ◽  
Vol 1028 ◽  
pp. 15-20
Author(s):  
Muhammad Abdan Syakuur ◽  
Yati Maryati ◽  
Togar Saragi ◽  
Risdiana
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Magnetic Impurity ◽  
Magnetic Moments ◽  
Magnetic Behavior ◽  
Partial Substitution ◽  
X Ray Diffraction ◽  
Magnetic Susceptibility Data ◽  
Susceptibility Data ◽  
Volume Unit

Structure and magnetic properties of electron-doped superconducting cuprates have been investigated in order to study the effect of magnetic impurity to its physical properties. Here, we reported structure and magnetic properties of Eu1.88Ce0.12Cu1-yZnyO4+α-δ (ECCZO) with y = 0 and 0.03. The properties of ECCZO have been studied from X-ray diffraction data and temperature dependence of magnetic susceptibility data, to elucidate the effect of partial substitution of non-magnetic impurity Zn for Cu to its structure, Tc and the value of magnetic moments per unit volume extracted from susceptibility data in normal state. Magnetic-susceptibility measurements were carried out down to 2 K on-field cooling at 5 Oe for Eu1.88Ce0.12Cu1-yZnyO4+a-d with y = 0 and 0.03. For ECCZO sample with y = 0 and d = 0.0669 indicated the change of magnetic behavior from paramagnetic to diamagnetic below 12 K which is addressed to the Tc onset of this samples. Diamagnetic behavior is observed starting from about 12 K. Above 12 K, all samples show paramagnetic behavior with the values of the magnetic moment in every volume unit increased with increasing Zn.

scholarly journals Effects of Li2O additive on structural, magnetic and electrical properties of Ni-Mg ferrite

2014 ◽  
Vol 38 (1) ◽  
pp. 7-18 ◽  
Author(s):  
Sheikh Mohi Uddin Rumy ◽  
Mahabub Alam Bhuiyan ◽  
MH Mesbah Ahmed ◽  
Kazi Hanium Maria ◽  
MA Hakim ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Spinel Ferrite ◽  
Lattice Parameter ◽  
Initial Permeability ◽  
Dielectric Behavior ◽  
Ferromagnetic Behavior ◽  
Xrd Pattern ◽  
Dielectric Constant Measurement ◽  
Academy Of Sciences ◽  
Magnetic And Electrical Properties

The effects of Li2O additives on the structural, magnetic and electrical properties of Ni0.5Mg0.5Fe2O4, prepared by conventional double sintering ceramic technique were investigated. The X-raydiffraction (XRD) pattern of the prepared samples showed single phase cubic spinel structure.Variation of lattice parameter has been observed with the variation of Li2O content. Theenhancement of bulk density has been observed for 2 mol% Li2O additive, but further increase inLi2O concentration, these values decrease. Enhancement of initial permeability (??) have beenobserved for the sample with 2 mol% Li2O additives while it decreases for higher concentration ofLi2O. The Curie temperature is found to decrease with the increase in Li2O additive. The resistivityincreases with increasing additive content and showed a significant dispersion with frequency,which is the normal ferromagnetic behavior. The dielectric constant (??) measurement showed thenormal dielectric behavior of spinel ferrite. Possible explanation for the observed features arediscussed. DOI: http://dx.doi.org/10.3329/jbas.v38i1.20198 Journal of Bangladesh Academy of Sciences, Vol. 38, No. 1, 7-18, 2014

scholarly journals Spin glass state structure theory and its application to explain experiments

2014 ◽  
Vol 70 (a1) ◽  
pp. C277-C277
Author(s):  
Jerzy Warczewski ◽  
Paweł Gusin ◽  
Daniel Wojcieszyk
Keyword(s):  
Magnetic Field ◽  
Spin Glass ◽  
Gaussian Distribution ◽  
Magnetic Moments ◽  
Magnetization Vector ◽  
Spin Glass State ◽  
Structure Theory ◽  
Average Kinetic Energy ◽  
General Description ◽  
Glass State

The authors have found the general description of all the eight fundamental magnetic structures and their symmetry groups (including spin glass state - sgs) with the use of the fibre bundle approach [1]. The structure of sgs turns out to consist in the Gaussian-like randomness of the orientations of all the separate atomic magnetic moments in the sample. It means that the magnetization vector M is also subject to Gaussian distribution. Thus the structure of the sgs is represented by the magnetization vector situated along the generatrix of a certain cone whose axis coincides with the direction of an internal spontaneous magnetic field indispensable for stability of the sgs in a sample [2]. The axis of the 3-dimensional Gaussian distribution mentioned above coincides also with the same direction. Every precession angle of M around this field makes the symmetry operation of sgs once the angle between M and this field remains constant. Thus the symmetry group of sgs turns out to be SO(2). The temperature dependence of magnetic susceptibility of sgs in the alloys CuMn [3] corresponds when heating to the gradual degeneration of the Gaussian distribution of the magnetization vector, and when cooling to its gradual recovery with no hysteresis. In both cases an internal spontaneous magnetic field mentioned above plays an essential role. The interrelation of this field, of the Gaussian distribution mentioned above, of the average kinetic energy of magnetic atoms and of the frustration of orientations of the magnetic moments placed on these atoms will be discussed.

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