Ca0.2 Cr0.15 Cu2.85 O8 Pb1.75 Sr2 Y Seshadri R, Maignan A, Hervieu M, Martin C, Raveau B, Rao C Journal of Solid State Chemistry 127 (1996) 64-71 Substitution of chromium for univalent copper in superconducting Pb2Sr2(Ca,Y)Cu3O8+d _cod_database_code 1001749 _database_code_amcsd 0013903 5.3860 5.4195 15.720 90 90 90 Cmmm atom x y z occ Pb1 0 .5 .3870 .875 Ca1 0 .5 .3870 .1 Sr1 0 0 .2208 Y1 0 0 0 Cu1 0 0 .5 .85 Cr1 0 0 .5 .15 Cu2 0 .5 .1084 O1 0 .5 .2625 O2 0 0 .385 O3 .25 .25 .1007