Potentials in a isolated single water molecule

LAMMPS LAMMPS Mailing List Mirror
1

Hi,

I am using the TIP3P model to simulate an isolated single water molecule. As a consequence of this model, I defined charges and LJ parameters and two harmonic constants for Coulomb, vdW, bond stretching and angle bending energies, respectively. My question is that inside that isolated water molecule is there any coulomic and vdW interactions between oxygen and hydrogens (of course I know that there are harmonic potentials between atoms) or they are assumed zero by LAMMPS because the atoms have the same molecular ID tag.

With best regards,
Soroush

2

The special_bonds command sets weighting factors on vdW and Coulomb
interactions between atoms that are part of the same bond, angle, dihedral.
Its default is 0.0 for those weighting factors, so within one water molecule
they are turned off. Note that most TIP3P models treat a water
molecule as a rigid body, in which case it doesn’t matter if you turn
off the intra-molecular pairwise terms or not, they sum to 0.0.

Steve