This modifier copies all particles, bonds and other data elements multiple times to visualize periodic images of a system.

The Operate on list in the lower panel lets you select the types of data elements that should be replicated by the modifier. By default, the modifier extends the simulation cell appropriately to encompass all generated images of the system. If not desired, you can turn off the Adjust simulation box size option to keep the original simulation cell geometry. You should be aware, however, that this produces an inconsistent state: The size of the periodic domain then no longer fits to the number of explicit images embedded in the domain.


Number of images - X/Y/Z

These values specify how many times the system is copied in each direction.

Adjust simulation box size

Extends the simulation cell to match the size of the replicated system.

Assign unique IDs

This option lets the modifier assign new unique IDs to the copied particles or bonds. Otherwise the duplicated elements will have the same identifiers as the originals, which may cause problems with other modifiers (e.g. the Manual selection modifier), which rely on the uniqueness of identifiers.


The modifier does not assign new molecule IDs to replicated atoms. The copies will have the same values of the Molecule Identifier property as the original atoms.

See also

ReplicateModifier (Python API)