Two Structural Blocks in HgBa2CuO4+δ

All the high Tc superconductors are structurally composed of two different blocks, the perovskite and the rock salt. Based on this fact, we developed a model to calculate the interaction between the two structural blocks. But the model could not deal with the superconductors with one Cu–O plane, such as Bi2Sr2CuOy (2201) phase and HgBa2CuO4+δ (1201) phase. Here we modify our model, dealing with HgBa2CuO4+δ in a different way in which the unit cell is still divided into two blocks, and the combinative energy between the blocks in HgBa2CuO4+δ with different δ value is calculated. It is shown that the reaction of the different blocks also closely related with the superconductivity in this compound.