== How to make the periodic image real? ==

At times one wants to give all those periodic images a true shape, i.e. one wants to duplicate the cell contents. How can this be achieved?

Assume we have a file '''cluster.xyz''' containing a cluster of calcium-silicate-hydrate (CSH)-gel. The box is a cuboid with 88 Angstroem length. Then, we duplicate this cluster in the y and z direction as follows:
{{{
./molecuilder --change-box "88,0,88,0,0,88" -i cluster.xyz --repeat-box "1,2,2
}}}

That is:
 * first, we use ''--change-box'' to set the correct box dimensions, essential for this operator and not contained in the ''xyz'' format,
 * Next, we parse the file ''-i''.
 * And finally, we call ''--repeat-box'' which duplicates the cell contents in x and y direction, creating a 1x2x2 grid out of the initial box containing the cluster.