Ba2 Cu3 O7 Y Beech F, Miraglia S, Santoro A, Roth R Physical Review B35 (1987) 8778-8781 Neutron study of the crystal structure and vacancy distribution in the superconductor Ba2YCu3O9-d _cod_database_code 1008353 _database_code_amcsd 0016264 3.8198 3.8849 11.6762 90 90 90 Pmmm atom x y z Ba1 .5 .5 .1839 Y1 .5 .5 .5 Cu1 0 0 0 Cu2 0 0 .3547 O1 0 0 .1581 O2 .5 0 .3779 O3 0 .5 .3776 O4 0 .5 0