      file (normally given the terminal identifier .sph).  This contains an atom record 
       for each centre with the occupancies set to the sphere radii. 
       This file is now used to produce molecular graphics objects rather than
       directly producing them in HOLE. This has the advantage of allowing the
       separation of the process allowing the combination of the results
       of more than one  HOLE run and/or 
       This is useful for analysis of the route found using
       molecular gra