Structure and Superconducting Characteristics of a Defective (<RM>Bi</RM>1.6<RM>Pb</RM>0.4) (<RM>Sr</RM>1.8<RM>Ba</RM>0.2) (<RM>Ca</RM>1.96<RM>Lu</RM>0.04) <RM>Cu</RM>3Oy Superconductor
Full pattern decomposition was applied to the X-ray diffraction patteren of a single phase orthorhombic (Bi1.6Pb0.4) (Sr1.8Ba0.2) (Ca1.96Lu0.04) Cu3Oy superconductor. Delocalization of the Sr atoms induces terracing of the Cu/Ca/Cu superconducting stacking up to 0.6 Å, in the range of the c-axis coherence length. This yields a three dimensional character of the conduction evidenced in the resistivity measurements also. The effect is direct consequence of the loss of symmetry implied by the orthorhombic structure.