Dear Elliot, the answer could be: generally speaking, results should change not so much because energy differences are known to converge quite rapidly with respect to the cutoff . However, no answer could be given without more details.
Indeed, the change of the properties with respect to ecutwfc/ecutrho strongly depends on the pseudo potential. So: which elements you are dealing with? Which type of pseudo potentials? Norm conserving or ultrasoft? In any case tests would be needed. Giovanni > On 06 Jul 2015, at 00:22, Elliot Menkah <[email protected]> wrote: > > Hello Everyone, > How does or to what extent does changing your ecut along with ecutrho > affect evaluation of results from computations? > For instance if you used 60Ry to compute 'delta H' for reactants and you > use 40Ry to compute 'delta H' for products. > > Reduction to 40 Ry was because some jobs with 60 Ry took too long a time > only not to converge even after 100 iterations. > > Thank you. > > Kind Regards, > Elliot > > -- > Elliot S. Menkah > Research Student - Computational Chemistry/ Computational Material Science > Theoretical and Computational Chemistry > Dept. of Chemistry > Kwame Nkrumah UNiversity of Sci. and Tech. > Kumasi > Ghana > > Tel: +233 243-055-717 > > Alt Email: [email protected] > [email protected] > > > > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum > -- Giovanni Cantele, PhD CNR-SPIN c/o Dipartimento di Fisica Universita' di Napoli "Federico II" Complesso Universitario M. S. Angelo - Ed. 6 Via Cintia, I-80126, Napoli, Italy e-mail: [email protected] Phone: +39 081 676910 Skype contact: giocan74 ResearcherID: http://www.researcherid.com/rid/A-1951-2009 Web page: http://people.na.infn.it/~cantele _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
