DIELECTRIC-CONSTANT AND CONDUCTIVITY OF ER2CU2O5

Structural data, electrical transport and dielectric properties are re ported for Er2Cu2O5. Similar to La2CuO4, this cuprate oxide reveals a two-dimensional CuO2 network. At low temperatures and high frequencies the electrical transport is dominated by hopping conductivity process es. The dielectric constant epsilon approximate to 9.0(5) has been det ermined from high frequency measurements. At high temperatures and low frequencies d.c. conductivity contributions dominate and characterize Er2Cu2O5 as a conventional semiconductor with a gap E(G) = 1.4 eV.