F Rb 
 1.0000000000000000
     3.3792108708136217   -0.0000000000000000    0.0000000000000000
    -0.0000000000000000    3.3792108708136217    0.0000000000000000
     0.0000000000000000    0.0000000000000000    3.3792108708136217
 F   Rb 
   1   1
Selective dynamics
Cartesian
  0.0000000000000000  0.0000000000000000  0.0000000000000000   T   T   T
  1.6896054354068115  1.6896054354068115  1.6896054354068115   T   T   T