(today) SrRuO3 is a metallic ferromagnet. Its electrical resistivity is reported for temperatures up to 1000K; its Hall coefficient for temperatures up to 300K; its specific heat for temperatures up to 230K. The energy bands have been calculated by self-consistent spin-density functional theory, which finds a ferromagnetic ordered moment of 1.45µB per Ru atom. The measured linear specific heat coefficient γ is 30mJ/mole, which exceeds the theoretical value by a factor of 3.7. A transport mean free path at room temperature of ≈ 10Å is found. The resistivity increases nearly linearly with temperature to 1000K in spite of such a short mean free path that resistivity saturation would be expected. The Hall coefficient is small and positive above the Curie temperature, and exhibits both a low-field and a high-field anomalous behavior below the Curie temperature.65.40. Em,75.40.Cx,71.25.Pi,72.15.Eb,72.15.Gd

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Resistivity, thermopower, and Hall-effect measurements on large single crystals of the anatase form of TiO2 all indicate high mobility n-type carriers that are produced by thermal excitation from a density of ∼1018 cm−3 putatively present shallow donor states. The decrease of the mobility with increasing temperature is consistent with the scattering of carriers by the optical phonons of TiO2.

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