SLABCC: Total energy correction code for charged periodic slab models
Description
The surface of solids or their interface with the gas phase is often modelled by a slab, periodic in two dimensions and repeated artificially in the third. When studying charged systems, a compensating background charge is required to avoid the divergence of the Coulomb energy. However, the interactions between the periodic images of the localized charge and between the localized charge and its neutralizing background can cause significant errors in the total energy. We have implemented the correction scheme proposed by Komsa and Pasquarello (2013), which estimates the error in the total energy by modelling the distribution of the localized extra charge with Gaussian functions at different sites, and comparing its energy in the periodic and in the isolated case. The program is user-friendly and robust, it is automated for simple cases while keeping the flexibility for the advanced users to handle non-trivial ones.