I'd say you'd only need ghost atoms (the basis functions you talk about) if you need to calculate the formation energy of the vacancy - the so-called BSSE correction.
Marcos On Wed, Apr 21, 2010 at 7:49 PM, Shelton Jr, William Allison < [email protected]> wrote: > I might be mistaken but doesn't siesta use atom-centered basis ? If so, > don't you need to put some basis functions on the vacant site ? > > Cheers > Bill > > > On 4/21/10 1:39 PM, "Marcos Veríssimo Alves" < > [email protected]> wrote: > > Just as a vacancy in real life, a vacancy in a DFT calculation is not an > addition, but a removal... :) > > All you need to do is to remove the undesirable atom(s) from the atom > coordinates list in your supercell. Of course, don't forget to update the > number of atoms. > > Marcos > > On Wed, Apr 21, 2010 at 7:30 PM, Shelton Jr, William Allison < > [email protected]> wrote: > Can siesta treat vacancies ? If so, how can it be added to the input file > ? > > Cheers > Bill > > >
