Semiconductor properties of iron oxides

Calculation of the electronic structure of freshly cleaved hematite surfaces suggest that the local electronic structure of the surface may be very different from the bulk 

Band gaps for goethite, lepidocrocite, akaganeite and 5-FeOOH are 2.10 eV, 2.06 eV, 2.12 eV and 1.94 eV, respectively. The conductivity of these materials is very low at room temperature (ca. 10 cm ) and increases somewhat as the sample 

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