抄録
The preparation and characterization of Pb0.18Bi0.93Ca1.02Sr1.02Cu1.6Ox, a lead-rich high-Tc phase, were studied (T(ρ=0)=105K). This compound crystallized in a pseudotetrag onal sturucture with at=0.541nm and ct=3.709nm, while a unique one-dimensional modulation with a wavelength of 4.7nm (_??_8.7b) was found along the b axis using transmission electron microscopy. This phase is not stabilized at lower temperature in air. It decomposes to the lead-free (or poor) high-Tc phase crystallizing in the convetional modulated structure 2.7nm(_??_5b).
