title Pb2 Y Sr2 Cu3 O8 (2-1-2-3 structure)
space   P 4/m m m 
a=3.813    c=15.76    core cu2
atom
  Pb      0.5     0.5     0.39
  Sr      0.0     0.0     0.22  
  Y       0.0     0.0     0.0
  Cu      0.5     0.5     0.11          Cu1
  Cu      0.0     0.0     0.5           Cu2
  O       0.0     0.5     0.10          O1
  O       0.5     0.5     0.25          O2
  O       0.0     0.0     0.38          O3
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