Crystal growth and physical properties of europium-based quaternary Chevrel phases (RE1−xEuxMo6S8; RE-Sm, Yb)

Rare-earth-based Chevrel phases constitute model systems to study both superconductivity and magnetic order but results may be hindered by the quality of the sample. Materials elaboration is thus essential to separate out extrinsic effects (secondary phases) from those due to the Mo 6 S 8 clusters and the rare-earth contribution. Crystal growth, transport and magnetic properties of the quaternary systems (RE, Eu)Mo 6 S 8 (RE-Sm, Yb) are presented. Different RE/Eu nominal ratios allowed to cover a large range of concentrations for single crystals. Superconducting transitions are narrow and as high as 9 K for ytterbium-rich samples, while the structural transition of the ternary EuMo 6 S 8 ( T s = 110 K) is largely diminished by the partial substitution of Eu by RE.