Dielectric Properties of Na_0.7CoO₂ and of the Superconducting Na_0.3CoO₂·1.3H₂O

We present dielectric properties of ceramic anhydrous Na0.7CoO2 and the superconducting Na(0.3)CoO(2)(.)13H(2)O materials. The presence of water which induces superconductivity also may increase the dielectric constant (epsilon) of the hydrated material. This is consistent with the predicted relationship between the high epsilon and the enhancement of T-c in high T-c superconductors. The anhydrous sample is porous and the transport is due to some percolation via the pores. The porosity is much higher for the hydrated material and the transport is ionic inside bulk water.