Synthesis, structure and physical properties ofYbNi3Al9.23

Abstract

The physical properties of YbNi3Al9.23(1), including the crystal structure, magnetization, specific heat, valence,and electrical resistivity, are reported. Single crystal x-ray diffractionreveals that the compound crystallizes with the rhombohedral space groupR32 and has unit cellparameters a = 7.2443(3) Å and c = 27.251(3) Å with some crystallographic disorder at Al sites. The compound orders antiferromagnetically atTN = 3 K despite the presence of strong ferromagnetic correlations, accompanied by aspin-flop-like transition to a moment-aligned state above 0.1 T. X-ray absorptionspectroscopy and magnetic susceptibility measurements indicate a localizedYb3 + electronic configuration, while the Sommerfeld coefficient forthe magnetically ordered state was determined as approximately135 mJ mol − 1 K − 2, suggesting moderately heavy fermion behavior. Therefore, these data indicate a balancebetween competing Ruderman–Kittel–Kasuya–Yosida (RKKY) and Kondo interactions inYbNi3Al9.23(1) with a somewhat dominant RKKY interaction that leads to a relatively high orderingtemperature.