Ba2 Ca0.09 Cu2.91 Fe0.09 O7.05 Y0.91 Suard E, Caignaert V, Maignan A, Raveau B Physica C 182 (1991) 219-227 The important role of pyramidal copper layers of the 123-structure in superconductivity. The oxides Ba2Y1-xCaxCu3-xFexO7 and Ba2Y1-xCaxCu3-xFexO6 _cod_database_code 1001496 _database_code_amcsd 0015035 3.8227 3.8227 11.6689 90 90 90 Pmmm atom x y z occ Y1 .5 .5 .5 .91 Ca1 .5 .5 .5 .09 Ba1 .5 .5 .1846 Cu1 0 0 0 Cu2 0 0 .3549 .955 Fe1 0 0 .3549 .045 O1 0 .5 .3782 O2 .5 0 .3771 O3 0 0 .1587 O4 .5 0 0 .92 O5 0 .5 0 .13