Magnetic scattering of conduction carriers in 3d transition-metal intercalates of M x TiS2 (M=Mn,Fe, Co,and Ni)

Galvanomagnetic measurements on layer-structured 3d transition-metal intercalates of M_xTiS₂ (M = Mn, Fe, Co, and Ni;x0.33) have been made over the temperature range 0.34–20 K. Resistivity minima and negative magneto-resistances are observed for paramagnetic Mn, Fe, and Ni intercalates with low guest concentrations (x0.1), as found in well-known dilute alloys. However, in the case of the weak-ferromagnetic phase of Co_xTiS₂ (0.10x0.33) with the Curie temperatureT _c =120–140 K, such anomalous behaviors are also observed, which is not commonly found in the magnetically ordered phases of various magnetic materials. With these data we have given qualitative discussions on the magnetic scattering process of conduction carriers. Further, some of the experimental results are discussed in connection with the band calculations for M_1/3TiS₂.