diff --git a/doc/src/fix_polarize.rst b/doc/src/fix_polarize.rst index 77a26baaaa..552015d0ea 100644 --- a/doc/src/fix_polarize.rst +++ b/doc/src/fix_polarize.rst @@ -72,16 +72,14 @@ coming from its area and surface charge density. For non-interface particles such as atoms and charged particles, the interface normal vectors, element area, and dielectric mismatch are -irrelevant. Their local dielectric value is used to rescale their given charge -when computing the Coulombic interactions. For instance, to simulate a cation +irrelevant and unused. Their local dielectric value is used internally to rescale their given +charge when computing the Coulombic interactions. For instance, to simulate a cation carrying a charge of +2 (in simulation charge units) in an implicit solvent with -a dielectric constant of 40, the cation's charge should be set to +2/40 = +0.05 and -its local dielectric constant property (defined in the -:doc:`atom_style dielectric `) should be set to 40. This will produce +a dielectric constant of 40, the cation's charge should be set to +2 and +its local dielectric constant property (defined in the :doc:`atom_style dielectric `) +should be set to 40; there is no need to manually rescale charge. This will produce the proper force for any :doc:`pair_style ` with the dielectric suffix. -As noted in :doc:`pair_style `, the charge (+0.05) will be scaled by the -local dielectric constant (40) to produce the appropriate charge (+2) during -force computation. It is assumed that the particles cannot pass through the interface +It is assumed that the particles cannot pass through the interface during the simulation because the value of the local dielectric constant property does not change. @@ -166,6 +164,8 @@ The *mr* keyword only applies to *style* = *polarize/bem/gmres*. It is the maxim The *omega* keyword only applies when using *style* = *polarize/bem/icc*. It is a relaxation parameter defined in :ref:`(Tyagi) ` that should generally be set between 0 and 2. +Note that the local dielectric constant (epsilon) can also be set independently using the :doc:`set ` command. + ---------- *polarize/bem/gmres* or *polarize/bem/icc* compute a global 2-element vector diff --git a/doc/src/pair_dielectric.rst b/doc/src/pair_dielectric.rst index ef1f186021..9489872416 100644 --- a/doc/src/pair_dielectric.rst +++ b/doc/src/pair_dielectric.rst @@ -77,15 +77,12 @@ Description All these pair styles are derived from the corresponding pair styles without the *dielectric* suffix. In addition to computing atom forces -and energies, these pair styles compute the electrical field vector +and energies, these pair styles compute the electric field vector at each atom, which are intended to be used by the :doc:`fix polarize ` commands to compute induced charges at interfaces between two regions of different dielectric constant. -These pair styles should be used with :doc:`atom_style dielectric `, -which uses atom charges rescaled by their local dielectric constant. See the note in -:doc:`fix polarize ` about properly setting ion charge given a -local dielectric constant. +These pair styles should be used with :doc:`atom_style dielectric `. The styles lj/cut/coul/long/dielectric, lj/cut/coul/msm/dielectric, and lj/long/coul/long/dielectric should be used with their kspace style counterparts, diff --git a/examples/PACKAGES/dielectric/in.confined b/examples/PACKAGES/dielectric/in.confined index f487cbc1f0..0f9dab7bba 100644 --- a/examples/PACKAGES/dielectric/in.confined +++ b/examples/PACKAGES/dielectric/in.confined @@ -7,7 +7,7 @@ # Dielectric constants can be set to be different from the input data file variable epsilon1 index 20 -variable epsilon2 index 10 # must be the same as the local epsilon defined in data.confined +variable epsilon2 index 10 variable data index data.confined