Repeating Group
Opens the Repeating group dialog to establish repeating units, SRU polymers or link nodes.
    
How to create a repeating group
     
        
-     Select the Repeating Group tool then select the structure you would like to group. 
-     Then the repeating group dialog opens. 
-     Select the repetition pattern and set the repetition range you prefer, then click OK. 
After the dialog closes, the repetition unit is established.