Electronic Properties of CuO2 Layers in High Tc Materials
The high Tc materials of La-Sr-Cu-O and of Y-Ba-Cu-O structures are both investigated by the use of a simple LCAO model. The local densities of states have shown both two-dimensional and one-dimensional behavior within different energy regions. Around Fermi level the dimensionality and the type of van Hove singularities become important for the enhancement of the critical temperature. The BCS parameters like the superconducting gap, critical temperature and the Debye frequency were calculated and their dependence on the density of states has been illustrated.