Sr3TlFe2O8 tP20 123

• Fe-O-Sr-Tl
• Fe-O-Pb-Sr-Tl
• magnetic properties
• Moessbauer spectra
• electronic and electrical properties
• isomer shift
• quadrupole splitting
• conductor
• chalcogen
• high-tc superconductor
• cuprate
• intermediate valence
• tetragonal