On Fri, Sep 9, 2016 at 9:30 AM, Daniel Stoeffler < [email protected]> wrote:
Surprisingly, the computation time is huge no sir: "unsurprisingly" the computation time is huge. The computational complexity of a calculation with hybrid functionals goes as (Nk*Nb)^2*Npw log(Npw) or so, where Nk=number of k-points, Nb=number of occupied bands, Npw=number of plane waves; with GGA functionals, as Nk*Nb*Npw log(Npw) or Nk*Nb*Npw^2 could you try to explain me how to reduce the computation time > first of all you may try to reduce one of the sums over k-points using options nq1,nq2,nq3, as explained in the example for hybrid. For a metal, not sure it works well, though. Since you are using UltraSoft PseudoPotentials, try option "tqr=.true." (real-space treatment of augmentation functions): it should give a significant speedup. Another significant improvement is contained in the forthcoming 6.0 version of QE, but it doesn't work yet for USPP Paolo -- Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
_______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
