Electrical resistivity studies carried out on (Er1-xPrx)2Fe17 (0.4 ≤ x ≤ 1.0) compounds show that they all possess metallic behaviour in the temperature range 16-400 K. Resistivity at low temperatures shows a T2 dependence, implying that electron-spin wave scattering is dominant in this temperature range. At higher temperatures, the resistivity is due to s-d interaction.

K. V.S. Rama Rao

Band structure

Crystal Structure

electric conductivity

Electric contacts

Electromagnetic wave scattering

Electronic structure

Fermi level

High temperature effects

Iron compounds

Magnetic properties

RARE EARTH COMPOUNDS

CRYSTAL FIELD PARAMETERS

ELECTRON SPIN WAVE SCATTERING

PRESSURE CONTACTS

RARE EARTH IRON INTERMETALLICS

S D INTERACTION

INTERMETALLICS

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Electrical resistivity studies on (er1-xprx)2fe17

Journal of Alloys and Compounds

The structural and magnetic properties of SmTb Fe17-x Alx (x=0-8) and SmTb Fe17-x Six (x=0-3.5) were investigated by x-ray-diffraction and magnetization studies. All the compounds stabilize in rhombohedral structure. The lattice parameters are found to increase with Al substitution whereas they are found to decrease with Si substitution. The rates of the decrease of saturation magnetization (Ms) value with the substitution of Al and Si are almost the same. The easy direction of magnetization (EMD) is in the ab plane up to an Al concentration of x=7 and has a tendency to shift towards the c axis at x=8. All the compounds with Si are seen to have the EMD in the ab plane. Electron-magnon scattering is seen to contribute to the electrical resistivity in both Al- and Si-substituted compounds; in the temperature range of 30-60 K and at higher temperatures, scattering due to phonons is observed. © 2005 American Institute of Physics.

Fulltext

Journal of Applied Physics

Effect of Al and Si substitutions on the magnetic properties of SmTbFe 17

The structural, electrical and magnetic properties of Dy 0.73Tb0.27Fe2-xMnx [x=0, 0.25, 0.5 and 1] have been investigated through X-ray diffraction studies and magnetization, Curie temperature and electrical resistivity measurements. The lattice parameter is found to increase with increasing Mn concentration. The saturation magnetization increases with increasing Mn concentration. The Curie temperature is found to decrease with increasing x, which is attributed to the net decrease in the exchange splitting of the spin-up and spin-down bands. Spin fluctuations have been observed in Dy0.73Tb0.27FeMn. All the materials are seen to exhibit metallic behavior and the contributions to the resistivity are discussed as due to the scattering due to magnons, s-d interactions and phonons, depending on the temperature. © 2004 Elsevier B.V. All rights reserved.

Journal of Magnetism and Magnetic Materials

Magnetic and electrical properties of Dy0.73Tb 0.27Fe2-xMnx [x=0, 0.25, 0.5 and 1]

The structural, electrical and magnetic properties of Ho 0.85Tb0.15Fe2Bx (x = 0,0.05,0.1,0.15) have been carried out through X-ray diffraction, electrical resistivity and magnetization measurements. All the alloys are found to crystallize in C15-type cubic Laves phase structure. It is observed that the lattice parameter is found to increase with increasing boron concentration, which may be due to the occupation of boron at interstitial sites. The magnetization and Curie temperature are found to be constant with the increase in x. The temperature variation of electrical resistivity shows a metallic behavior with an increase in resistivity with increasing boron concentration. The resitivity behavior is explained on the basis of electron-magnon scattering at low temperatures and electron-phonon scattering at high temperatures. © 2004 Elsevier B.V. All rights reserved.

Structural, electrical and magnetic properties of Ho0.85Tb 0.15Fe2Bx

The structural, magnetic and electrical properties of Ho 0.85Tb0.15Fe2Mnx (x = 0-0.15) have been characterized through X-ray diffraction, Curie temperature and electrical resistivity measurements. All the alloys are found to crystallize in C15-type cubic Laves phase structure. It is observed that the lattice parameter increases with increasing Mn concentration. The Curie temperature is found to decrease with increasing x, which is attributed to the net decrease in the exchange splitting of the spin-up and spin-down bands. All the materials are seen to exhibit metallic behavior with a decrease in the slope of ρ versus T curve near the Curie temperature. The resistivity behavior is explained on the basis of s-d scattering mechanism and electron-phonon interaction. Spin fluctuations have been observed through Curie temperature and resistivity measurements. © 2003 Elsevier B.V. All rights reserved.

Magnetic and electrical properties of Ho0.85Tb 0.15Fe2-xMnx (0, 0.5, 1.0, 1.5)

We have studied the magnetic, magnetocaloric and magnetotransport properties of RSn1+xGe1+x(R=Gd, Tb, and Er; x=0.1) series by means of magnetization, heat capacity and resistivity measurements. It has been found that all the compounds crystallize in the orthorhombic crystal structure described by the centrosymmetric space group Cmcm (No. 63). The magnetic susceptibility and heat capacity data suggest that all the compounds are antiferromagnetic. Large negative values of O in case of GdSn 1.1Ge0.9 and TbSn1.1Ge0.9 indicate that strong antiferromagnetic interactions are involved, which is also reflected in the magnetization isotherms. On the other hand ErSn1.1Ge 0.9 shows weak antiferromagnetic interaction. The heat capacity data have been analyzed by fitting the temperature dependence and the values of 0D and y have been estimated. Among these three compounds, ErSn 1.1Ge0.9 shows considerable magnetic entropy change of 9.5 Jkg K and an adiabatic temperature change of 3.2 K for a field of 50 kOe. The resistivity data in different temperature regimes have been analyzed and the dominant contributions have been identified. All the compounds show small but positive magnetoresistance. © 2013 Elsevier B.V. All rights reserved.

Magnetic, magnetocaloric and magnetotransport properties of RSn 1+xGe1+xcompounds (R=Gd, Tb, and Er; X=O.1)

A nitrogenation facility working in the pressure range 0–100 bar and temperature range 30–600°C was fabricated and the nitrides were prepared. There is an increase in the unit cell volume by about 8% for a nitrogen concentration of 2.7. Similarly there is an increase in the magnetization as well as the Curie temperature after nitrogenation for all the compounds. The increase in the magnetization is due to the increase in the average Fe moment as a result of lattice expansion following nitrogenation. The increase in the Curie temperature is explained on the basis of spin fluctuation theory. A tentative spin phase diagram is proposed based on the magnetization and ac magnetic susceptibility measurements. Upon nitrogenation, the resistivity of the samples increases by one order of magnitude still retaining the metallic behaviour. © 1995 IEEE

Journal	Data powered by TypesetJournal of Alloys and Compounds
Publisher	Data powered by TypesetElsevier BV
ISSN	09258388
Open Access	No