Superconducting transition and Raman spectrum of Y₁Ba ₂Cu₃O_7-x prepared by polymeric precursor synthesis

High-T_c superconducting Y₁Ba₂Cu ₃O_7-x bulk samples were prepared by polymeric precursor synthesis. Resistance, x-ray diffraction, and Raman scattering measurements were performed for sample characterization. The bulk specimen exhibited a sharp superconducting transition at 94.5 K with a 10%-90% transition width of 0.5 K. Four Raman active phonon modes were observed at frequences of 150, 337, 440, and 502 cm^-1 in the 120-700 cm^-1 region.