[gmx-users] restore pbc after a rotation

[XAvier Periole]

Dears,

I need to rerun a trajectory that has been rotated to orient a molecule
according to a reference. The pbc are therefore broken.

Would anyone know how to restore the correct position of the atoms  
inside
the unit cell after the rotation is applied. The rotation is actually  
applied around
only one axis (z, membrane normal).

Thanks for any suggestion.
XAvier.