New ternary aluminides RERh4Al15 (RE = La, Ce, Pr, Sm, Gd)

The aluminum-rich intermetallic rare earth compounds RERh4Al15 (RE = La, Ce Pr, Sm, Gd) were synthesized by arc melting of the elements under an argon atmosphere. The samples were characterized by powder X-ray diffraction which revealed a straight-forward agreement of the synthesized materials with tetragonal space group P4(2)/nmc, NdRh4Al15.37 structure type. The structures of CeRh4Al15 and PrRh4Al15 were refined from single-crystal X-ray diffraction data. CeRh4Al15 is a new correlated electron compound with Kondo interaction. There is no magnetic ordering above 0.05 K despite the localized Ce3+ magnetic moment behaviour near room temperature. The electronic specific heat, magnetic susceptibility and electrical resistivity indicate that the compound may be accidently poised near a magnetic quantum critical point. (C) 2019 Elsevier B.V. All rights reserved.