TY - JOUR
T1 - Magnetism and colossal magnetoresistance of the pseudo-ternary rare-earth transition-metal compounds, Eu14-xCaxMnSb11 (x < 3)
AU - Kim, Hyungrak
AU - Chan, Julia Y.
AU - Olmstead, Marilyn M.
AU - Klavins, Peter
AU - Webb, David J.
AU - Kauzlarich, Susan M.
PY - 2002
Y1 - 2002
N2 - The compounds, Eu14-xCaxMnSb11 (x < 3), have been prepared by heating the mixture of stoichiometric amounts of the elements, sealed in a quartz-jacketed Ta tube, in a two-zone furnace with Thigh = 1100 and Tlow = 1050 °C for 10 days. These compounds are isostructural with the Zintl compound Ca14AlSb11. The rare-earth transition-metal compounds crystallize in the tetragonal space group I41/acd, Z = 8, T = 90 K, a = 17.2235(7) and c = 22.6555(9) Å, V = 6720.7(5) Å3, and R1/wR2 (0.0413/0.1129) for x = 1.45 and a = 17.1737(7) and c = 22.5741(10) Å, V = 6657.9(5) Å3, and R1/wR2 (0.0392/0.1122) for x = 2.83. Temperature-dependent magnetic susceptibility measurement of the powder samples reveals complex magnetic interactions in the compounds and indicates a canted ferromagnetic configuration for Eu14-xCaxMnSb11. As the amount of nonmagnetic Ca increases to x = 2, the effective magnetic moment decreases from 29.9 to 27.9 μB/fu., and the paramagnetic Curie temperature of the compound increases from 82.4 to 86.4 K at 1000 Oe. The magnetotransport properties of one compound, Eu13CaMnSb11 (x = 1), were measured and show a close relation to its magnetic properties, especially in the low-temperature region. The influence of chemical substitution on the structural and physical properties of Eu14-xCaxMnSb11 will be discussed in terms of the site preferences of Ca doping into the four different Eu sites.
AB - The compounds, Eu14-xCaxMnSb11 (x < 3), have been prepared by heating the mixture of stoichiometric amounts of the elements, sealed in a quartz-jacketed Ta tube, in a two-zone furnace with Thigh = 1100 and Tlow = 1050 °C for 10 days. These compounds are isostructural with the Zintl compound Ca14AlSb11. The rare-earth transition-metal compounds crystallize in the tetragonal space group I41/acd, Z = 8, T = 90 K, a = 17.2235(7) and c = 22.6555(9) Å, V = 6720.7(5) Å3, and R1/wR2 (0.0413/0.1129) for x = 1.45 and a = 17.1737(7) and c = 22.5741(10) Å, V = 6657.9(5) Å3, and R1/wR2 (0.0392/0.1122) for x = 2.83. Temperature-dependent magnetic susceptibility measurement of the powder samples reveals complex magnetic interactions in the compounds and indicates a canted ferromagnetic configuration for Eu14-xCaxMnSb11. As the amount of nonmagnetic Ca increases to x = 2, the effective magnetic moment decreases from 29.9 to 27.9 μB/fu., and the paramagnetic Curie temperature of the compound increases from 82.4 to 86.4 K at 1000 Oe. The magnetotransport properties of one compound, Eu13CaMnSb11 (x = 1), were measured and show a close relation to its magnetic properties, especially in the low-temperature region. The influence of chemical substitution on the structural and physical properties of Eu14-xCaxMnSb11 will be discussed in terms of the site preferences of Ca doping into the four different Eu sites.
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U2 - 10.1021/cm010512s
DO - 10.1021/cm010512s
M3 - Article
AN - SCOPUS:0036124394
VL - 14
SP - 206
EP - 216
JO - Chemistry of Materials
JF - Chemistry of Materials
SN - 0897-4756
IS - 1
ER -