Arnab Senapati wrote: > Hello, > I was trying to run a simple LJ system. In the conf.gro box size is > 7.52 (cubic). But in the confout.gro the box size is 9.1. Is this > possible? Yes, since it happened. :-) If you're trying to understand what it is that you've done that has caused the change, you'd best start by telling us what you did. Mark