On Mon, Dec 24, 2012, Vijay Manickam Achari wrote:
>
> I am trying to simulate only water molecules in a box for 100 ns. I am
> using 1445 water molecules in a box size 50.499 43.396 20.071 and
> the parameter input file I use is as below:
>
> After 38 ns the simulation terminates saying "ERROR: max pairlist
> cutoff must be less than unit cell max sphere radius!" in output file.
Your box is too small in the z-direction. Basically, twice the cutoff (which
in your case is 9) plus skinnb (which defaults to 2, I think, but check your
output file) has to be less than the smallest box dimension (which is 20.07).
So you just barely qualify at the beginning. If you get a fluctuation
in volume that reduces the z-length even slightly, you will trigger this
error.
So, you need to either make the cutoff smaller, or the box bigger. You might
be able to get away with setting skinnb to 1.0. That will slightly slow down
the calculation (not by much, I think) and you might not have to make any
other changes.
...dac
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Received on Mon Dec 24 2012 - 06:30:03 PST
