Dear lammps users,
To be consistent with minimum image convention, the cutoff distance (rc) in a simulation should be less than half of the box length. In one of my simulations of pure water with box dimensions as Lx=27.088, Ly=23.446 and Ly=12.072A. i was able run the simulation upto 15A cutoff distance with out any errors … but i was surprised to see simulation runs with out any error even when rc>L/2. can any one comment on this… how does it calculate energies if rc>L/2 ?
RAVI KUMAR REDDY A
IISc Bangalore
Dear lammps users,
To be consistent with minimum image convention, the cutoff distance (rc)
in a simulation should be less than half of the box length. In one of my
simulations of pure water with box dimensions as Lx=27.088, Ly=23.446 and
Ly=12.072A. i was able run the simulation upto 15A cutoff distance with
out any errors ... but i was surprised to see simulation runs with out any
error even when rc>L/2. can any one comment on this... how does it
calculate energies if rc>L/2 ?
minimum image conventions do not apply to LAMMPS for almost all of its
modules, since LAMMPS embeds each subdomain with real copies of atoms
(usually referred to as "ghost atoms"), even multiple copies of the same
atom. thus you can have a cutoff that is larger than half the shortest box
length.
axel.