title  K2 Ni F4 structure
space I 4/m m m
a=3.8    c=13.2  core=ni
atom
  K     0.0    0.0    0.36
  Ni    0.0    0.0    0.0    
  O     0.0    0.5    0.0	o1
  O     0.0    0.0    0.18	o2
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