On Sat, Jan 30, 2016 at 3:38 PM, Małgorzata Wawrzyniak-Adamczewska <[email protected]> wrote: > Hello Stefano, > > > > the problem is that i would like to study the band structure etc. around the > K point in graphene and graphene with adatoms with SO. With the accuracy of > order 10^-4 I think I will not be able to see some important details.
on the other hand, i think it would be very advisable to do some sensitivity analysis with respect to what level of systematic and numerical accuracy is possible for the eigenvalue spectrum. chances are, that you may just be digging around in numerical noise or that any systematic differences may due to technicalities and not the underlying physics. i.e. (small) changes to cutoffs, grids, number of atoms, type of pseudopotentials, number of processors may cause changes of equal or greater magnitude and thus would then render findings questionable (to put it mildly). axel. > > Best wishes, > > > > Malgorzata Wawrzyniak-Adamczewska > > Adam Mickiewicz University, Poznan, Poland > > > > Message: 2 Date: Fri, 29 Jan 2016 14:13:33 +0100 From: stefano de gironcoli > <[email protected]> Subject: Re: [Pw_forum] accuracy of the energies printed > to file To: [email protected] Message-ID: <[email protected]> > Content-Type: text/plain; charset="utf-8" do you really need to print the > eigenvalues with 10^-7 eV accuracy ? stefano On 29/01/2016 14:08, Ma?gorzata > Wawrzyniak-Adamczewska wrote: > > Dear QE users and developers, I was wondering if there is a possibility to > increase the accuracy of the energies printed in the e.g. scf.out file or > bands.out file? I find the accuracy of D^-4: > ------------------------------------------------------------------------------------------------------- > k = 0.0000 0.0000 0.0000 ( 2289 PWs) bands (ev): -21.2789 -21.2789 -9.3618 > -9.3618 -4.7450 -4.7450 -4.7357 -4.7357 1.2876 1.2876 2.0573 2.0573 2.2604 > 2.2604 4.3273 4.3273 4.9921 4.9921 6.6656 6.6656 6.6734 6.6734 8.2476 8.2476 > 9.4082 9.4082 9.8358 9.8358 10.9914 10.9914 13.5952 13.5952 > ----------------------------------------------------------------------------------------------------- > and would like to increase it to D^-7. Thank you in advance, Malgorzata > Wawrzyniak > > > > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum -- Dr. Axel Kohlmeyer [email protected] http://goo.gl/1wk0 College of Science & Technology, Temple University, Philadelphia PA, USA International Centre for Theoretical Physics, Trieste. Italy. _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
