[gmx-users] grompp error

[chris.neale at utoronto.ca]

>> ERROR: The cut-off length is longer than half the shortest box vector
>> or longer than the smallest box diagonal element. Increase the box
>> size or decrease rlist.

> try to "Increase the box size or decrease rlist."  <= as ERROR  
> message suggests

Yes, technically you could decrease rlist (rcoulomb actually in this  
case), but in that case make sure that you know what you are getting  
into. I would advise against that unless you are sure that you  
understand the implications. I think that this is a particularly  
dangerous error message and should be modified in future gromacs  
distributions.

PS, I see that you actually do have the line:
pcoupl               = berendsen
which I had not seen previously when I said:
> WARNING: did you even turn on constant pressure? I think not.  
> However  you have set some variables for constant pressure ... this  
> is not the  same as turning it on. Look at the mdp options for  
> pressure coupling.
So I was incorrect there.