E.A. Giess, B.E. Argyle, et al.
Materials Research Bulletin
The bcc structure I4̄3d-Td6(Th3P 4) occurs as a defect structure in 2:3 compounds of rare-earth elements with S, Se, and Te, or as an inverted structure in 4:3 compounds with group VA elements. The structural, electric, and magnetic properties of the metallic 4:3 compounds and the 2:3 rare-earth semiconductors have been investigated with specific reference to gadolinium, for which the S ground state gives the minimum crystal field effect. Gd4Bi3 and Gd4Sb3 are both ferromagnetic with a saturation magnetization obeying the spin-wave T32 law up to 0.8 of the Curie temperature. The Curie temperature Tc varies in the solid solution system Gd4Sb3Single Bond sign Gd4Bi3 with composition from 260°to 340°K. The semiconducting compound Gd 2Se3(ρRT=3 Ω cm) has been found to be antiferromagnetic below TN=6°K. Solution of Gd in the holes of the defect Th3P4 structure decreases the electrical resistivity without a measurable variation of lattice constant (a 0=8.718 Å). With increasing conductivity the material changes from antiferromagnetic to ferromagnetic. At the composition Gd 2.1Se2.9 the Curie temperature is Tc=80°K with ρRT=1.4×10-3 Ω cm. The relation between Curie temperature and electrical resistivity has been examined by introducing the same spin concentration into Gd2Se3 by Eu2+ doping. The semiconductor Eu0.5Gd 1.6Se2.9 is paramagnetic. However, Y0.5Gd 1.6Se2.9 has low resistivity and is ferromagnetic below Tc=47°K. © 1964 The American Institute of Physics.
E.A. Giess, B.E. Argyle, et al.
Materials Research Bulletin
M.W. Shafer, T.R. McGuire, et al.
Journal of Applied Physics
T.R. McGuire, P.R. Duncombe, et al.
Journal of Applied Physics
Y. Yeshurun, A.P. Malozemoff, et al.
Physical Review B