  By using band structure calculations of quantum mechanical theory, some
important peaks of DoS (Density of States) were obtained and classified based
on crystal structure laws of cuprate superconductivity. In particular, the
orbital interactions of the in-plane and out-of-plane ions of the copper-oxygen
plane were investigated. The position, half-width, and height of DOS peak
features were collected for all 35 typical curate systems which have critical
temperature maximum data from the works of literature. By training test of 7
common machine learning algorithms, the relationship between the Tc maximum
values and these orbital interaction parameters were mined. It was found that
the key features of the orbital interaction affecting the Tc maximum were not
only the flat band but also a new interaction between core orbitals in a deeper
energy band position.
