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The temperature dependent thermopower of Bi x TiS 2 ( x = 0 , 0.05, 0.15, 0.25) was investigated in the temperature range from 7 to 300 K. The thermopower of all samples show a metallic behavior with diffusion thermopower dominating at high temperatures and a peak of phonon-drag contribution at low temperatures. They could be scaled to S = S ∗ × S ( T / T ∗ ) , indicating that the Bi intercalation does not change the scattering mechanism. The thermopower should be attributed to the special lens-shaped Fermi pockets. With increasing Bi intercalation, the Fermi pockets expand, and each Bi atom transfers five electrons to the host layers.

The resistivity and thermopower of the misfit-layered (Bi, Pb)–Sr–Co–O system with different Pb concentration were investigated. The thermopower is surprisingly large and T -independent with metallic resistivity at high temperatures, suggesting a narrow band contribution. The resistivity starts to increase below about 90 K, while no change can be seen in the thermopower, which is evidence of Anderson localization in a disordered structure.

The temperature dependent thermopower S a ( T ) of the Bechgaard salt (TMTSF)2PF6 was measured along the highly conducting a axis. Surprisingly, an abrupt change of gap value was found at 8 K. The gap values revealed by the thermopower measurements within the SDW phase are much smaller than that revealed in the resistivity measurement, implying the existence of magnetic-polaron hopping below T SDW .

The transport properties, thermopower (TEP), thermal conductivity (κ) and resistivity (ρ) are investigated for the optimally doped (x = 0.15) Nd1−xCexCuO4 (NCCO) single crystal, after annealing in flowing nitrogen at 900 °C for different times. Both TEP and ρ are interpreted in a two-band model with an electron broad band and a hole-like narrow band. After suitable annealing, the bandwidth (Γ) of the narrow band decreases abruptly, resulting in an anomalous change of TEP at 300 K. At the same time, κ increases considerably because of the increasing thermal conductivity of charge carriers, and a peak emerges around 75 K, due to the interaction between carriers and phonons.