Hi everyone,
I am trying to figure out if is correct to use Siesta to perform a DeltaSCF calculation (neutral system minus charged system) for a 2D system (a metal slab). I am interested in calculating the IP and EA for the slab and compare it with the work function (which for my understanding should be equal to the work function). The work function I guess is clear that we have to take from the Fermi energy the position of the vacuum level. For the IP and EA I have tried to use the DeltaSCF procedure in which we can remove/add fractions of charge to the cell and take the difference from the neutral calculation. My question is if this procedure would be valid for a slab calculation. I know that the madenlung correction is switched off for periodic calculations. How to take this correction into account for periodic system since now the box is charged? How does siesta calculates the energy in this case (because it should diverge!).? Thanks for your help in advance! Amaury.
