Dear all:
In the pair_style buck/coul/long command, the different between buck/coul/long and buck/coul/cut is that:only the LJ cutoff can be specified since a Coulombic cutoff cannot be specified for an
individual I,J type pair.
What does it means?
|
dear <name in favorite unreadable foreign character set>,
Dear all:
In the pair_style buck/coul/long command, the different between
buck/coul/long and buck/coul/cut is that:only the LJ cutoff can be
specified since a Coulombic cutoff cannot be specified for an
individual I,J type pair.
What does it means?
you have to read the documentation more carefully! it says that
buck/coul/cut and buck/coul/long add a coulomb contribution similar
to the corresponding lennard-jones styles. so you have to read that
documentation, too.
the coul/long variant in both cases adds a screening term to
coulomb interactions that can be combined with a kspace style
to include long range contributions to the interaction potential
and forces. as a consequence of the global way how interactions
are computed in lattice sums, you can only have one global cutoff
for coulomb interactions (for consistency). this cutoff depends
on the alpha used in the screening that is typically automatically
determined through the kspace commands (or rather the other way
around).
cheers,
axel.