Abstract
I investigate the structural properties, resistivity and magnetic susceptibility of dilute La, Ce, Pr, Gd, Dy and Lu impurities in ZrAl{sub 2}. The cerium alloy shows anomalies in volume and resistivity increment, which indicate a fractional valence of it. Gd, Dy and Lu alloys of the Zr{sub 1-x}RE{sub x}Al{sub 2} type show the different than Ce and large volume, resistivity and susceptibility anomalies which are for x<0.5 interpreted by only the partial dissolving of RE impurities in ZrAl{sub 2}. For x>0.5 the Curie-Weiss paramagnetic temperature of Zr{sub 1-x}Gd{sub x}Al{sub 2} is analyzed and the agreement between the theoretical and the experimental results is found. The lattice parameters, volume of the unit cell and the susceptibility of ZrM{sub 1.2}All{sub 0.8} (M=Fe,Co,Cu) were investigated. The physical quantities of Zr alloys measured versus temperature are very similar to these which are characteristic for the spin fluctuation systems. The temperature dependences of the lattice constant, of the thermal expansion coefficient, and the intensities of thermal expansion coefficient, and the intensities of the x-ray diffraction lines (hkl) at room temperature and below, show a similar anomalies in CeFe{sub 2}, CeCo{sub 2} and CeNi{sub 2}, especially below {approx}100 K, which are strongly correlated with the change
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Hafez, M H.E.S.
[1]
- Uniwersytet Slaski, Katowice (Poland). Inst. Fizyki
Citation Formats
Hafez, M H.E.S.
Magnetic and structural investigations of the rare earth and transition metals intermetallic compounds of the laves phase - type.
Poland: N. p.,
1991.
Web.
Hafez, M H.E.S.
Magnetic and structural investigations of the rare earth and transition metals intermetallic compounds of the laves phase - type.
Poland.
Hafez, M H.E.S.
1991.
"Magnetic and structural investigations of the rare earth and transition metals intermetallic compounds of the laves phase - type."
Poland.
@misc{etde_101506,
title = {Magnetic and structural investigations of the rare earth and transition metals intermetallic compounds of the laves phase - type}
author = {Hafez, M H.E.S.}
abstractNote = {I investigate the structural properties, resistivity and magnetic susceptibility of dilute La, Ce, Pr, Gd, Dy and Lu impurities in ZrAl{sub 2}. The cerium alloy shows anomalies in volume and resistivity increment, which indicate a fractional valence of it. Gd, Dy and Lu alloys of the Zr{sub 1-x}RE{sub x}Al{sub 2} type show the different than Ce and large volume, resistivity and susceptibility anomalies which are for x<0.5 interpreted by only the partial dissolving of RE impurities in ZrAl{sub 2}. For x>0.5 the Curie-Weiss paramagnetic temperature of Zr{sub 1-x}Gd{sub x}Al{sub 2} is analyzed and the agreement between the theoretical and the experimental results is found. The lattice parameters, volume of the unit cell and the susceptibility of ZrM{sub 1.2}All{sub 0.8} (M=Fe,Co,Cu) were investigated. The physical quantities of Zr alloys measured versus temperature are very similar to these which are characteristic for the spin fluctuation systems. The temperature dependences of the lattice constant, of the thermal expansion coefficient, and the intensities of thermal expansion coefficient, and the intensities of the x-ray diffraction lines (hkl) at room temperature and below, show a similar anomalies in CeFe{sub 2}, CeCo{sub 2} and CeNi{sub 2}, especially below {approx}100 K, which are strongly correlated with the change of the Ce-ion valence. The intensity measurements of the diffraction lines of CeM{sub 2} (M=Ni,Co) samples suggest that these substances have to be considered as a combination of two MgCu{sub 2} structures with two different lattice constants a{sub 1} and a{sub 2} (a{sub 2} > a{sub 1}) where the number of the crystal unit cells of two different phases is in relation 9(a{sub 1}):1(a{sub 2}). As a proof we try to explain abnormal change of the Ce-ion valence, basing on the Anderson model. The calculations, presented here, consider the sample as a special kind of an `alloy` which is a mixture of two different phases. (Abstract Truncated)}
place = {Poland}
year = {1991}
month = {Dec}
}
title = {Magnetic and structural investigations of the rare earth and transition metals intermetallic compounds of the laves phase - type}
author = {Hafez, M H.E.S.}
abstractNote = {I investigate the structural properties, resistivity and magnetic susceptibility of dilute La, Ce, Pr, Gd, Dy and Lu impurities in ZrAl{sub 2}. The cerium alloy shows anomalies in volume and resistivity increment, which indicate a fractional valence of it. Gd, Dy and Lu alloys of the Zr{sub 1-x}RE{sub x}Al{sub 2} type show the different than Ce and large volume, resistivity and susceptibility anomalies which are for x<0.5 interpreted by only the partial dissolving of RE impurities in ZrAl{sub 2}. For x>0.5 the Curie-Weiss paramagnetic temperature of Zr{sub 1-x}Gd{sub x}Al{sub 2} is analyzed and the agreement between the theoretical and the experimental results is found. The lattice parameters, volume of the unit cell and the susceptibility of ZrM{sub 1.2}All{sub 0.8} (M=Fe,Co,Cu) were investigated. The physical quantities of Zr alloys measured versus temperature are very similar to these which are characteristic for the spin fluctuation systems. The temperature dependences of the lattice constant, of the thermal expansion coefficient, and the intensities of thermal expansion coefficient, and the intensities of the x-ray diffraction lines (hkl) at room temperature and below, show a similar anomalies in CeFe{sub 2}, CeCo{sub 2} and CeNi{sub 2}, especially below {approx}100 K, which are strongly correlated with the change of the Ce-ion valence. The intensity measurements of the diffraction lines of CeM{sub 2} (M=Ni,Co) samples suggest that these substances have to be considered as a combination of two MgCu{sub 2} structures with two different lattice constants a{sub 1} and a{sub 2} (a{sub 2} > a{sub 1}) where the number of the crystal unit cells of two different phases is in relation 9(a{sub 1}):1(a{sub 2}). As a proof we try to explain abnormal change of the Ce-ion valence, basing on the Anderson model. The calculations, presented here, consider the sample as a special kind of an `alloy` which is a mixture of two different phases. (Abstract Truncated)}
place = {Poland}
year = {1991}
month = {Dec}
}