Oxygen trapped by rare earth tetrahedral clusters in Nd4FeOS6: Crystal structure, electronic structure, and magnetic properties

摘要

Single crystals of Nd4FeOS6 were grown from an Fe-S eutectic solution. Single crystal X-ray diffraction analysis revealed a Nd4MnOSe6-type structure (P6(3)mc, a=9.2693(1) angstrom, c=6.6650(1)angstrom, V=495.94(1) angstrom(3), Z=2), featuring parallel chains of face-sharing [FeS6x1/2](4-) trigonal antiprisms and interlinked [Nd4OS3](4+) cubane-like clusters. Oxygen atoms were found to be trapped by Nd-4 clusters in the [Nd4OS3](4+) chains. Structural differences among Nd4MnOSe6-type Nd4FeOS6 and the related La3CuSiS7- and Pr8CoGa3-type structures have been described. Magnetic susceptibility measurements on Nd4FeOS6 suggested the dominance of antiferromagnetic interactions at low temperature, but no magnetic ordering down to 2 K was observed. Spin-polarized electronic structure calculations revealed magnetic frustration with dominant antiferromagnetic interactions. (C) 2015 Elsevier Inc. All rights reserved.