Abstract
It is found that direct Madelung sums within a sphere of large radius obtained with a laptop converge rapidly if, and only if, one calculates also the charge of the cluster, and adds a shell of charge at radius . A simple program running through the lattice provides Madelung potentials within a part in a thousand of the correct values in a few seconds of computation. It is illustrated for perovskite lattices. The corresponding calculation for a metal, positive charges embedded in a constant compensating negative charge distribution, is similarly successful.
- Received 16 February 2006
DOI:https://doi.org/10.1103/PhysRevB.73.212103
©2006 American Physical Society