Low-energy excitations in CeBiPt

Magnetic order in GdBiPt studied by x-ray resonant magnetic scattering

“…In contrast to GdBiPt, CeBiPt is an antiferromagnet characterized by a propagation vector q m = (1 0 0) and the ordered moments are collinear with the propagation vector along [1 0 0], 20 but with a reduced moment that may, in part, be attributed to crystalline electric field (CEF) effects. 30 Unfortunately, XRMS measurements do not allow a direct extraction of the ordered moment in GdBiPt, but earlier specific heat measurements 16 estimated an entropy of ∼0.8 R ln 8 associated with the magnetic transition close to the value expected for full moment ordering without CEF effects. The entropy associated with the corresponding magnetic transitions for the Nd, Tb and Dy compounds were considerably less than R ln(2J+1) expected for the full Hund's rule J multiplet, indicating the importance of CEF effects in these compounds.…”

Magnetic structure of the antiferromagnetic half-Heusler compound NdBiPt

“…As similar moment reduction to CEF effects was reported for CeBiPt, where the ordered moment corresponds to the magnetic moment of the Γ 8 ground state of the Ce 3+ion. 28,36 The effect of the CEF is to lift the 10-fold degeneracy of the J = 9 2 multiplet of the Nd 3+ -ion through an electrostatic interaction. For a Nd 3+ -ion sitting in a cubic environment, the CEF splitting is expected to result in a new ground state consisting of a Γ 6 doublet, and two quartets, Γ (1) 8 and Γ (2) 8 .…”