Crystal Structure, Magnetic and Transport Properties of CeRu_1–xNi_xAl (x = 0.5)

Abstract

Single crystals of CeRu 0.5 Ni 0.5 Al can be obtained from a Ce-Ni melt using elements as starting materials. The presented compound crystallizes in the orthorhombic space group Pnma (no. 62) with a = 700.38(7), b = 416.92(4) and c = 1562.84(16) pm in the LaNiAl * Prof. Dr. S. M. Kauzlarich

Synthesis and Theoretical Investigations of the Solid Solution CeRu1–xNixAl (x = 0.1–0.95) Showing Cerium Valence Fluctuations

“…In the orthorhombic structures, cerium, aluminum, and the transition metal each occupy two distinct crystallographic sites. The two positions of the transition metal are mixed-occupied by ruthenium and nickel, comparable to what has been reported for CeRu 0.5 Ni 0.5 Al before . The crystal structure is described best by using the reduced coordination polyhedron surrounding the (Ru/Ni) sites in the shape of trigonal prisms of the compositions [(Ru/Ni)1Ce 6 ] and [(Ru/Ni)2Ce 2 Al 4 ].…”

“…In the case of CeRuAl, the strong interactions between cerium and ruthenium are explained. Recently, the solid solution CeNi 0.5 Ru 0.5 Al has been reported 7 which crystallizes in the orthorhombic CeRuAl structure and exhibits magnetic properties similar to those of the ternary phases for T > 20 K, but for T < 20 K, an abrupt increase in χ(T) is found near 10 K. Herein we report the full series of the solid solution CeRu 1−x Ni x Al with 0.1 ≤ x ≤ 0.95 from the standpoint of structure and properties, combined with theoretical calculations in order to explain the features found.…”

“…The two positions of the transition metal are mixed-occupied by ruthenium and nickel, comparable to what has been reported for CeRu 0.5 Ni 0.5 Al before. 7 The crystal structure is described best by using the reduced coordination polyhedron surrounding the (Ru/Ni) sites in the shape of trigonal prisms of the compositions [(Ru/Ni)1Ce 6 ] and [(Ru/Ni)2Ce 2 Al 4 ]. The prisms are fused together over (Ce 2 ) edges to form branched, corrugated chains running along [100] that are further interlocked with chains of the other kind along the crystallographic c axis and a shift of x/2.…”

Gradual Cerium Valence Change in the Solid Solution CeRu1–xPdxAl (x = 0.1–0.9)

“…A similar behavior has been found in CePd 1– x Rh x Al 15. We have recently reported on the magnetic properties of the solid solution CeRu 1– x Ni x Al, where the compounds crystallize for a large range of x ( x = 0.1–0.8) in the LaNiAl type structure 6,16. All members in this series exhibit intermediate cerium valences, with a shift of the cerium valence to more trivalent character with increasing Ni content.…”