Physical properties and giant magnetoresistance in RNiSb compounds

The physical properties of RNiSb (R=rare earth) have been investigated by magnetization, resistivity and magnetoresistance measurements. The light rare earth compounds are metallic, while those with Tb, Dy, Ho, are semiconductors with a giant negative magnetoresistance. With the exception of the Pauli-paramagnets LaNiSb and YNiSb, all those compounds have a Curie-Weiss magnetism. CeNiSb and NdNiSb are ferromagnetic probably with an additional modulated component for Ce, the heavy rare earths TbNiSb, DyNiSb and HoNiSb compounds order antiferromagnetically at low temperatures. (C) 1998 Elsevier Science S.A.