TY - JOUR
T1 - Structure, magnetism, and colossal magnetoresistance (CMR) of the ternary transition metal solid solution Ca14-xEuxMnSb11 (0 < x < 14)
AU - Kim, Hyungrak
AU - Olmstead, Marilyn M.
AU - Klavins, Peter
AU - Webb, David J.
AU - Kauzlarich, Susan M.
PY - 2002/8
Y1 - 2002/8
N2 - The solid solution of the ternary transition metal Zintl phase Ca14-xEuxMnSb11 (0 < x < 14) has been prepared by heating a mixture of stoichiometric amounts of the elements in a two-zone furnace with Thigh = 1100°C and Tlow = 1050°C. The ternary transition metal compounds crystallize in the tetragonal space group I41/acd and are isostructural with the Zintl compound Ca14AlSb11. The lattice parameters of the Ca14-xEuxMnSb11 compounds linearly increase with increasing Eu substitution for Ca. The Eu atoms preferentially occupy the Ca(2) site first and subsequently occupy Ca(4), Ca(1), and Ca(3), in order, among the four crystallographically inequivalent Ca sites. Temperature-dependent magnetic susceptibility measurements of the solid solution reveal that Eu replacement for Ca induces complex magnetic interactions in the compound, from simple ferromagnetic interactions for Ca14MnSb11 to ferrimagnetic interactions for Eu14MnSb11, because of the Eu2+(4f7) magnetic moment. The paramagnetic Curie temperature of the Ca14-xEuxMnSb11 compounds shows an interesting change with varying x, and the magnetic easy axis gradually changes in the solid solution from perpendicular (for Ca14MnSb11) to parallel (for Eu14MnSb11) to the crystal c axis. The electrical transport properties of the Ca14-xEuxMnSb11 (x = 0, 3, 11) compounds show a close relation to their magnetic properties and are compared to the previous results for Ca14-xEuxMnSb11 (x = 13, 14). The influence of Eu doping on the structural and physical property of Ca14-xEuxMnSb11 is discussed in terms of the site preferences of Eu for the four different Ca sites.
AB - The solid solution of the ternary transition metal Zintl phase Ca14-xEuxMnSb11 (0 < x < 14) has been prepared by heating a mixture of stoichiometric amounts of the elements in a two-zone furnace with Thigh = 1100°C and Tlow = 1050°C. The ternary transition metal compounds crystallize in the tetragonal space group I41/acd and are isostructural with the Zintl compound Ca14AlSb11. The lattice parameters of the Ca14-xEuxMnSb11 compounds linearly increase with increasing Eu substitution for Ca. The Eu atoms preferentially occupy the Ca(2) site first and subsequently occupy Ca(4), Ca(1), and Ca(3), in order, among the four crystallographically inequivalent Ca sites. Temperature-dependent magnetic susceptibility measurements of the solid solution reveal that Eu replacement for Ca induces complex magnetic interactions in the compound, from simple ferromagnetic interactions for Ca14MnSb11 to ferrimagnetic interactions for Eu14MnSb11, because of the Eu2+(4f7) magnetic moment. The paramagnetic Curie temperature of the Ca14-xEuxMnSb11 compounds shows an interesting change with varying x, and the magnetic easy axis gradually changes in the solid solution from perpendicular (for Ca14MnSb11) to parallel (for Eu14MnSb11) to the crystal c axis. The electrical transport properties of the Ca14-xEuxMnSb11 (x = 0, 3, 11) compounds show a close relation to their magnetic properties and are compared to the previous results for Ca14-xEuxMnSb11 (x = 13, 14). The influence of Eu doping on the structural and physical property of Ca14-xEuxMnSb11 is discussed in terms of the site preferences of Eu for the four different Ca sites.
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U2 - 10.1021/cm020065w
DO - 10.1021/cm020065w
M3 - Article
AN - SCOPUS:0036677836
VL - 14
SP - 3382
EP - 3390
JO - Chemistry of Materials
JF - Chemistry of Materials
SN - 0897-4756
IS - 8
ER -