I have started with one particle consist of 506 atoms and 25950 bonds. This works fine but when replicate same particle 9 times LAMMPS create that error. So I also think that overflow 32 bit counter happens here.
so please check the output of that run. you should see the extreme growth when you look at the lines following:
Finding 1-2 1-3 1-4 neighbors …
the number of 1-4 neighbors should be very large.
Previously I have used fix rigid command instead of making bonds to perform DPD simulation. Fix rigid was used for the time integration of rigid body and fix nve for the nonrigid solvent. Which gives me unexpected pressure in the system. I have read several literature related to DPD and all of them used constant bonds to keep particles together.
“keeping particles together” is different from making them “rigid”.
question is: how many bonds need to be created for that purpose?
i.e. how is determined which particles need to be bound to which?
and are these bonds in addition to the non-bonded interactions or to replace the non-bonded interactions?
the default setting in LAMMPS is the second option, but my hunch is that this is not the model you describe.
so my assertion that this is an ill-conceived or incorrectly realized model remains.