Ba Cu2 O7 Sr Tl Y Huve M, Martin C, Michel C, Maignan A, Hervieu M, Raveau B Journal of Physics and Chemistry of Solids 54 (1993) 145-152 Influence of the size of alkaline earth cations on the structural distortion and transport properties of the semiconducting 1212 - type cuprates TlBa2-xSrxLnCu2O7 _cod_database_code 1001525 _database_code_amcsd 0013240 3.8421 3.8421 12.2064 90 90 90 P4/mmm atom x y z occ Tl1 .085 0 0 .25 Ba1 .5 .5 .2098 .5 Sr1 .5 .5 .2098 .5 Y1 .5 .5 .5 Cu1 0 0 .3638 O1 0 .5 .391 O2 0 0 .179 O3 .5 .5 0