Crystal structure of the high T c (107 K) superconducting phase in Pb-Bi-Sr-Ca-Cu-O
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The crystal structure of the high Tc superconducting phase in a Pb-doped Bi-Sr-Ca-Cu-O system (nominal composition Pb0.3Bi1.7Sr2Ca3Cu4OY) with a zero-resistance temperature of 107 K was determined with transmission electron microscopy. The investigation shows that the crystal structure, which is different from the Pb-free one, is monocline with dimensions a=0.532 nm, b=0.383 nm, c=3.71 nm, α=β=90° and γ=134.8°. A distinct change of wave vector of incommensurate modulation was also observed.Keywords:
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