Dear Davide Yes, the procedure is correct, and you can easily compare the results with those obtained in a GTO framework. If you neglect/minimize basis sets issues, pseudopotentials issues, numerical noise, etc., you generally obtain close eigenvalues in PW/GTO frameworks, using the same xc functional.
> Then I should have something more or less comparable amongst > different isolated system and in which the HOMO is always negative > and the LUMO is either very close to 0 or positive. This depend on the functional, of course... There are tons of papers on ionization energy, electron affinity and related DFT errors. Best Giuseppe Quoting Tiana Davide <davide.ti...@epfl.ch>: > Dear all > > > I would like to check I am doing the correct things. > > > I need to compare the eigenvalues of some atoms and molecules. > > I am following this procedure: > > > 1) pw in a cube cell bigger enough to exclude any interaction with > its neighbours. > > 2) adding the "assume_isolated='makov-payne'" option in the input > > 3) add the "Corrected vacuum level" found at the bottom of the > output to each eigenvalue. > > > Then I should have something more or less comparable amongst > different isolated system and in which the HOMO is always negative > and the LUMO is either very close to 0 or positive. > > This is what I would expect using LCAO programs like Gamess or > Gaussian, can I expect something similar using pw and mp correction? > > > Best Regards > > ?Davide -- ******************************************************** - Article premier - Les hommes naissent et demeurent libres et égaux en droits. Les distinctions sociales ne peuvent être fondées que sur l'utilité commune - Article 2 - Le but de toute association politique est la conservation des droits naturels et imprescriptibles de l'homme. Ces droits sont la liberté, la propriété, la sûreté et la résistance à l'oppression. ******************************************************** Giuseppe Mattioli CNR - ISTITUTO DI STRUTTURA DELLA MATERIA v. Salaria Km 29,300 - C.P. 10 I 00015 - Monterotondo Stazione (RM) Tel + 39 06 90672836 - Fax +39 06 90672316 E-mail: <giuseppe.matti...@ism.cnr.it> http://www.ism.cnr.it/en/staff/giuseppe-mattioli/ ResearcherID: F-6308-2012 _______________________________________________ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum