Chemical Trends in High-T sub c Ferroelectricity and Superconductivity.

High temperature (strong coupling) superconductors and ferroelectrics are completely localized on Villars global quantum structural diagrams. The microscopic origin of this localization is identified as a fundamentally new kind of giant lattice instability which is entirely different from the small displacive instabilities associated with low temperature (weak coupling) superconductivity and ferroelectricity.