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Magnetic properties of RE5Ir2X (RE = Y, Gd-Ho, X = Sn, Sb, Pb, Bi) and magnetocaloric characterization of Gd5Ir2X
被引:19
|作者:
Schaefer, Konrad
[1
]
Schwickert, Christian
[1
]
Niehaus, Oliver
[1
]
Winter, Florian
[1
]
Poettgen, Rainer
[1
]
机构:
[1] Univ Munster, Inst Anorgan & Analyt Chem, D-48149 Munster, Germany
关键词:
Rare earth intermetallics;
Magnetic properties;
Magnetocaloric effect;
Mossbauer spectroscopy;
SN-119;
MOSSBAUER-SPECTROSCOPY;
CRYSTAL-STRUCTURE;
COMPUTER-PROGRAM;
ISOMER-SHIFTS;
SYSTEM;
SB-121;
TB;
PD;
DY;
LU;
D O I:
10.1016/j.solidstatesciences.2014.06.010
中图分类号:
O61 [无机化学];
学科分类号:
070301 ;
081704 ;
摘要:
Systematic phase analytical studies of the systems RE-Ir-X (X = Sn, Pb, Sb, Bi) led to 15 new stannides, plumbides, antimonides and bismuthides with the composition RE5Ir2X. The compounds have been synthesized and characterized by X-ray powder diffraction. The structures of Gd5Ir2Sb and Dy5Ir2Bi have been refined from single crystal X-ray diffractometer data: Mo5SiB2 type, I4/mcm, a = 775.2(2), c = 1361.3(5) pm, wR2 = 0.0933, 404 F-2 values, 16 variables for Gd5Ir2Sb and a = 767.5(1), c = 1368.9(3) pm, wR2 = 0.0694, 571 F-2 values, 16 variables for Dy5Ir2Bi. Magnetic measurements of Gd5Ir2X (X = Sn, Pb, Sb, Bi), Tb5Ir2X (X = Sn, Pb, Sb, Bi), Dy5Ir2Pb, Dy5Ir2Bi and Ho5Ir2Pb indicate ferromagnetic transitions at T-c = 154.3, 159.3, 124.4, 119.3, 99.2, 98.2, 65.5, 68.6, 45.1, 35.6 and 23.5 K, respectively. Gd5Ir2Bi and Gd5Ir2Sb show an additional antiferromagnetic transition at T-N = 118.5 and 91.0 K. The magnetocaloric effect of Gd5Ir2X (X = Sn, Pb, Sb, Bi) in terms of the isothermal entropy change Delta S-m is -7.3(3), -6.5(3), -8.7(3) and -9.0(3) J kg(-1), K-1 at temperatures of 153, 157, 120 and 126 K for a 5 T field change. Sn-119 Mossbauer spectra of Gd5Ir2Sn at 78 K show a huge transferred hyperfine field of 21.9(1) T and an isomer shift of 1.94(1) mm s(-1), typical for stannides. Sb-121 Mossbauer spectra of Gd5Ir2Sb at 78 K show a transferred hyperfine field of 14.2(3) T and an isomer shift of -7.45(8) mm s(-1) reflecting the antimonide character. (C) 2014 Elsevier Masson SAS. All rights reserved.
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页码:66 / 73
页数:8
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