Ni substitution effect on magnetic and transport properties in metallic ferromagnet Co3Sn2S2

We investigated the magnetic and transport properties of polycrystalline (Co1-xNix)(3)Sn2S2(0 <= x <= 1) to ascertain the magnetism of the new metallic ferromagnet Co3Sn2S2. In Co3Sn2S2 magnetization does not saturate up to 5.5T at 10K, and the estimated saturation moment (rho(s)) is small (similar or equal to 0.2 mu(B) per Co atom). In (Co1-xNix)(3)Sn2S2, the electrical resistivity shows metallic behavior without a hump but has a kink at T-C. The T-C and magnetic susceptibility gradually decrease with increasing x, and there is no antiferromagnetic phase throughout the full range of composition. These results indicate that Co3Sn2S2 is a weak itinerant ferromagnet; while, the same order of the Rhodes-Wohlfarth p(c)/p(s) value as CoS2 suggests the existence of a localized moment. (c) 2006 Elsevier B.V. All rights reserved.