The atoms of the cluster are specified by one-line commands to be included in the cluster definition box. The list of commands ends with the keyword end. Apart from that, the order of the commands is arbitrary and they can be repeated as many times as needed. There are three different king of commands (click on them for further details):

• atom symbol x y z

• layer symbol x y z a b α₁ α₂

• surface symbol x y z a type

In addition to that, there is one more command to specify the location of the emitter atoms (use this commands as many times as needed):

• emitter x y z

Only atoms contained within a sphere or parabolid centered at a given reference point are included in the cluster, with a maximum number of atoms specified by the user (see the corresponding parameters in the EDAC front page). However, some restrictions may apply to the total number of atoms.