Mixed-metal flux synthesis of quaternary RMn2TrxZn20-x compounds with Tr = Al, In

摘要

Eighteen new intermetallic compounds RMn2TrxZn20-x (2 < x < 7; R = rare-earth metal; Tr = Al, In) were synthesized using low-melting mixtures of (Tr/Zn) as a solvent. Structural refinement using single-crystal X-ray diffraction data shows that the compounds are substituted variants of the cubic CeCr2Al20-type structure (Fd-3m, Z = 8; unit cell parameters vary from a = 14.1152(3)angstrom for YbMn2Al5.3Zn14.7 to a = 14.8125(4)angstrom for SmMn2In5.9Zn14.1). The Zn and Tr elements show site preferences in the indium compounds, but not in the aluminum analogs. The substitution of trielide element for zinc modifies the valence electron count of the compounds to allow for the incorporation of Mn into the structure. Magnetic susceptibility data show no evidence of magnetic ordering down to 3 K. (c) 2006 Elsevier Inc. All rights reserved.