STRUC    ALAT=8.995
         PLAT=1.0 0.0 0.0
              0.0 1.0 0.0
              0.0 0.0 1.0
SITE     ATOM=O  POS=1/4 1/4 1/4
         ATOM=O  POS=3/4 3/4 3/4
         ATOM=Ag POS=0.0 0.0 0.0
         ATOM=Ag POS=1/2 1/2 0.0
         ATOM=Ag POS=1/2 0.0 1/2
         ATOM=Ag POS=0.0 1/2 1/2