Crystalline electric field in RNiSb compounds investigated by inelastic neutron scattering

The crystalline electric field (CEF) of RNiSb (R = Ce, Pr, Nd, Tb, Dy, Ho, Er and (Er0.1Y0.9)) has been investigated by inelastic neutron scattering measurements and compared with the theoretical CEF-simulations. The determined CEF level schemes explain the different orientations of the magnetic moments between the different compounds in this series; they are directed along a fourfold crystal axis in DyNiSb and ErNiSb, along a twofold one in TbNiSb and HoNiSb with an additional moment rotation in TbNiSb below Neel temperature. The CEF model was applied to analyse the electrical resistivity. In CeNiSb, the Kondo behaviour is reconfirmed, and the ground state of PrNiSb is shown to be a nonmagnetic singlet. (C) 1999 Elsevier Science B.V. All rights reserved.