[ase-users] Arranging atoms in the cell of a POSCAR file

[Clemens Barth]

Dear all.

I have a POSCAR file, which describes the positions of atoms within a 
cell. When I load this
file with, e.g., VMD the atoms are somewhat split up into groups. For 
instance, one part is located
at the upper border of the cell along +z whereas the other part is at 
the lower border of the
cell along -z - the atoms do not form one complete structure as one 
would expect. However, when
repeating the cell all is okay - the structure is well represented. - 
somebody told me that this 'problem'
is somewhat normal when doing VASP calculations

However, due to some specific reasons I would like to rearrange the atom 
positions such that they
are centered in the cell and that they are together forming one complete 
structure.
Is there a mean to do this by some ASE function? Is there some function, 
which makes some
'order' in the cell without destroying the structure itself?

Any help is highly appreciated.

CB.