mBJ was designed for solids and it could well be that for a molecules the procedure to determine a proper "c"-value (average of grad rho/rho) does not work and you get unphysical values due to the vacuum region.
In such a case I can only recommend to remove case.in0_grr, and set a proper grad rho/rho value in case.grr yourself. A good estimate would be to set it to a similar value as a "similar" bulk-system (eg. diamond) would have. Also: Make sure you modified case.inm and set PRATT mixing ! Ricardo Faccio schrieb: > Dear users > > I've been working on the isolated molecule catechol > (http://en.wikipedia.org/wiki/Catechol) in order to see how mBJ affects > its HOMO-LUMO gap. > > The initialization and convergence at GGA-PBE level went fine, obtaining > a energy gap of 4.0 eV in concordance with other DFT codes. > > Afther this I proceeded in order to incorporate the modified > Becke-Johnson potential (MBJ), but I found several problems in > determining the position of the Fermi level. What we see is a clear > problem of finding enough eigenvalues, which arelower than the number of > valence electrons. Therefore we proceed according to the userguide by: > -changing the Fermi-Method (tetra, gauss and temp) -> error persist > - changing Rmt to similar values increasing the lmax to12 -> error persist > - increasing energy window in case.klist and case.in1c in order to > catch the lost eigenvalues -> error persist > It seems to be a problem on a big change introduced by the mBJ potential > which induces important divergences iat the lapw1. > > ###################### > > case.output1up > > ###################### > > EIGENVALUES ARE: > 1.4443359 1.4892578 1.8037109 1.8486328 1.8486328 > 1.8935547 1.9384766 1.9384766 > 1923 EIGENVALUES BELOW THE ENERGY -9.00000 > ******************************************************** > The problem always occurs in the first cycle of the mBJ procedure after > lapw1, with few eigenvalues as you can see. > > I succeed applying this methodology to bulk systems such as TiO2. > > Any suggestion? > > Best regards > > Ricardo > > > > ------------------------------------------------------------------------- > Dr. Ricardo Faccio > Prof. Adjunto de F?sica > Mail: Cryssmat-Lab., C?tedra de F?sica, DETEMA > Facultad de Qu?mica, Universidad de la Rep?blica > Av. Gral. Flores 2124, C.C. 1157 > C.P. 11800, Montevideo, Uruguay. > E-mail: rfaccio at fq.edu.uy <mailto:rfaccio at fq.edu.uy> > Phone: 598 2 924 98 59 > 598 2 929 06 48 > Fax: 598 2 9241906 > Web: http://cryssmat.fq.edu.uy/ricardo/ricardo.htm > --------------------------------------------------------------------------------- > > > ------------------------------------------------------------------------ > > _______________________________________________ > Wien mailing list > Wien at zeus.theochem.tuwien.ac.at > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien -- P.Blaha -------------------------------------------------------------------------- Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna Phone: +43-1-58801-15671 FAX: +43-1-58801-15698 Email: blaha at theochem.tuwien.ac.at WWW: http://info.tuwien.ac.at/theochem/ --------------------------------------------------------------------------