Developers Manual:Ion-Ion interaction

From OctopusWiki
Revision as of 00:56, 21 November 2007 by Xavier (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search

The ion-ion interaction term is tricky to treat, as is an inifinte sum with a finite result. The standard way to handle it is through an Ewald sum, however in Octopus this is done in a slighlty different way.

The energy term (per volume unit) is:

is a sum over atoms inside the cell, only over atoms outside and is over all the atoms.

The first separation that is

as the first term is the energy of a finite system, the second can be seen as the interaction of the particles in the cell with the potential generated by the particles outside, we will call it .