Crystal structure and physical properties of new ternary silicides R4T13X9 (R, rare earth or uranium; T, rhodium or iridium; X, silicon or germanium)

Autor: Pierre Bordet, Pascal Lejay, J. X. Boucherle, A. Vernière, Niels Keller, J.L. Tholence, J. Chenavas
Rok vydání: 1995
Předmět:
Zdroj: Journal of Alloys and Compounds. 218:197-203
ISSN: 0925-8388
Popis: New ternary silicides have been discovered with the general formula R4T13X9, where R is a rare earth or uranium, T is rhodium or iridium and X is silicon or germanium. The crystal structure has been solved on a single crystal. The symmetry is orthorhombic with space group Pnmm. The lattice constants for Er4Ir13Si9 are a = 18.848(3) A , b = 10.918(2) A and c = 3.9153(5) A . The formation of the various members of this new family is in competition with that of the well-known ternary silicides RT3X2. Their existence as a function of the various elements (rare earth and transition metals) is discussed. The magnetic properties of the iridium-based compounds are presented. All the samples containing a paramagnetic rare earth are magnetically ordered at low temperature. U4Ir13Si9 and U4Ir13Ge9 exhibit two ordering transition temperatures: 18 and 6.4. K for the silicide and 25 and 7 K for the germanide.
Databáze: OpenAIRE