Syntheses, Structures, and Theoretical Studies of New Ternary Antimonides β‐RECoSb3 (RE = La–Nd, Sm)

Abstract

AbstractFive new intermetallic ternary cobalt antimonides β‐RECoSb3 have been prepared by solid state reactions and characterized by single‐crystal X‐ray diffraction. The title compounds crystallize in β‐RENiSb3‐type structure, Pbcm (No.57), Z = 8, with a = 12.985(4)–12.5530(13) Å, b = 6.1603(18)–6.1043(4) Å, c = 12.166(4)–12.0267(12) Å for RE = La, Ce, Pr, Nd, and Sm. Their structures feature the anionic Sb square nets and CoSb6 octahedron layers that are separated by RE3+ cations along the a axis. The structural relationship among parent‐type (RECrSb3), α‐type (RENiSb3), and β‐type (RECoSb3) has been presented. The electronic band structure of β‐LaCoSb3 has been calculated with the aid of the tight‐bonding linear muffin‐tin orbital (TB‐LMTO) method and the results suggest that the three types of RETSb3 are metallic in both b and c directions and the electrical conductivities along the a direction are relatively weak. The magnetic calculations indicated that the rare‐earth atoms would be the only source for the magnetic properties. Therefore, β‐type Co analogues should be magnetically identical to the corresponding Ni members. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)