PART IVSUPERCONDUCTIVITYOxidation StatesThe oxidation states of the elements that form high Tc composites have to be in the ionization state necessary to form the half-filled shell insulators (Circular Model). Superconducting planes of copper (II) and O2 -- form full shell compounds leaving no electron (hills) or positron (holes) to disrupt superconductivity. The Circular Model of the Atom exhibits where the necessary balance between cations and anions to form neutral superconducting materials is found. For example, it has been exhibited that extra lanthanum, as well as oxygen can lead to loss of superconductivity. The high Tc insulating elements, Bi, Y, La, Tl, Ba, all serve the purpose of shielding the copper oxide planes from either positive or negative influence. Elements with half-filled shells opposite the flow direction act as insulators. The Cu2+ - O2- planes are effective conductors because there are no holes (positron sites - negative hemisphere) or humps (electron sites - positive hemisphere) to impede conductance. If there are oxidation states that are not back to the respective anion or cation polarity position, then it impedes conductivity. In agreement with the Circular Model of the Atom the Cu2+ ion is now a completely filled positive half-filled shell cation. |