Abstract
Incommensurate layer compounds (RES)xNbS2 are a new class of the intercalation compounds of NbS2; the x=1.2 and the x=0.6 compound have a stage-1 and a stage-2 structure, respectively. The results of the resistivity and the Seebeck coefficient measurements for several of them and the Pauli paramagnetic susceptibility of (LaS)1.2NbS2 are well interpreted with the rigid-band model by incorporating a large charge transfer from the intercalate RES layer to the host NbS2 layer. Large residual resistivities of the compounds are discussed in terms of the structural incommensurability. A logarithmic temperature dependence of the resistivity observed for the stage-2 compounds below -- 20, K is discussed in relation with the carrier localization. A fractional superconductivity has been observed for most of the samples below 2-- 6, K and its model based on the peculiar structure is proposed.
