Galvanomagnetic properties of vacancy lattices RNiSn (R=Ti,Zr,Hf)

The first results are reported of investigation of the galvanomagnetic properties of new interesting object - the vacancy intermetallic lattices - RNiSn (R=Ti, Hf, Zr), in which vacancies of Ni (in contrast to the structure of RNi2Sn) form a regular lattice. The measurements were made in a wide range of temperatures (0.1 < T < 250) K in magnetic fields up to 40 kOe. It was found that the compounds RNiSn are characterized by low, close to minimal metal conductivity σ ∼ σmin ∼ 100 (Ohmxcm)-1. Temperature dependences of resistivity ρ(T) of the compounds RNiSn have a form, unusual for normal nonmagnetic intermetallic systems: for some compounds as the temperature drops below room one, ρ(T) grows without visible saturation in the range of ultralow temperatures. The possible reasons of low temperature anomalies of galvanomagnetic properties of RNiSn compounds are analysed