¹¹⁹Sn Mössbauer study of high-temperature superconductor YBa₂Cu₃O_7-y doped with Sn

All samples were prepared at the same condition: prefired at 900°C for 10 hours in oxygen and sintered at 1000°C for 30 hour in oxygen. The zero resistance temperature decreased with increasing Sn content. ¹¹⁹Sn Mössbauer spectra of YBa₂Cu_2.8Sn_0.2O_7-y superconductor from 80 K to room temperature were measured. The sites occupied by Sn were indicated. The variation of the isomer shifts and quadrupole splittings were observed in the superconducting transition region. The observation of the resonant line intensity shown the change of the lattice rigidity.