New post from thomfrauen1950
Self-consistent charge correction in VASP
Supercell models are often used to calculate the electronic structure of local deviations from the ideal periodicity in the bulk or on the surface of a crystal. When the defect or adsorbent is charged, a jellium counter charge is applied to maintain overall neutrality, but the interaction of the artificially repeated charges has to be corrected, both in the total energy and in the one-electron eigenvalues and eigenstates. This becomes paramount in slab or wire calculations, where the jellium counter charge may induce spurious states in the vacuum. The BCCMS at the University Bremen in collaboration with Max-Planck-Institute Hamburg has developed a procedure for a self-consistent potential correction (SCPC), which corrects for the spurious effects of the repeated charge automatically without any postprocessing. The method and its tests are described in PRL 126, 076401 (2021). SCPC is part of the official VASP package as of version 6.2. For users of version 5, a patch (as well as a manual and examples) can be obtained from Peter Deák ([email protected]) or Mauricio C. Silva ([email protected]).