We report a detailed study of the microstructure of the new class of high-Tc superconductors, Pb2Sr2ACu3O8, by transmission electron microscopy and diffraction. Several new structural and superstructural variants are observed for A=Eu+Sr, Dy+Ca/Sr or Dy+Sr. Approximately 50% of the individual crystals analyzed displayed weak violation of the c centering present in x-ray macroscopic structure determination, and superstructure variants with modulation vectors parallel to a and/or b were observed in 25% of Eu+Sr the crystals analyzed. In the A=Dy+Sr structures only, structure modulations were observed along  and  directions.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics