STRUCTURAL AND MAGNETIC-PROPERTIES OF THE TERNARY RARE-EARTH (RE) COMPOUND SERIES LAINAU2, TOINAU2, LUINAU2, YINAU2

Results of structural, magnetic and heat capacity studies are reported for the REInAu//2 series (except europium). A crystallographic transformation from cubic to tetragonal structure occurs for the compounds with lanthanum, cerium, praseodymium and neodymium. With the exception of LaInAu//2, the phase transition has no observable effect on the magnetic susceptibility. Compounds formed with gadolinium, terbium, dysprosium and holmium order antiferromagnetically at low temperature. In this series YbInAu//2 is confirmed to be in an unstable valence state with the maximum 2J plus 1 equals 8 ground state degeneracy.