David wrote: > Is it infinite? Then use pbc=full Hi, I'd like to know: 1. how does "pbc=full" behave? 2. what is the major difference between "pbc=xyz" and "pbc=xyz"? I searched the manual, but cannot find any description about the option "pbc=full". Can someone show me a clue? Thanks so much in advance. Regards, Jian Zou