Dear Yao-Hong It seems that you are working in a very accurate way. I would only say that (maybe) d metals such as Cu hosted in sp semiconductors could benefit of a DFT+U treatment, but it is only my biased suggestion! Is it is the scf of the Cu-doped system that does not converge, or is it the BFGS? Best Wishes Giuseppe
On Tuesday, May 03, 2016 12:12:23 PM n16031320 wrote: > Dear Giuseppe: > > Thanks for your response, I use Ver.5.3.0 of QE and GGA in the form of PBE. > > About the type of pseudopotential, I use PAW from THEOS, according to the > website it said that PAW type is widely tested and no error is reported. > > I study some paper which is experiment, they dope with Ag and the percentage > up to 7%, so I think 6.25% may be ok. > > I studied the paper which is about experiment, it is said that SnSe doped > with Al, Pb and Cu for 2%,respectively, don't change lattice parameter too > much, > > so I decided to do the relax calculation instead of vc-relax first for doped > with Pb and Al for 6.25%, and the result show that the position of > atoms don't change too mush, > > then I check the total force is <0.0004 , I think the result of > relaxation is reasonable.  > > First I use 12 processors for the vc-relax calculation, now I use 48 > processors for the relax calculation,  > > the relax calculation for the doped with Al and Pb for 6.25% is done, but > doped with Cu for 6.25% is still running, maybe 6.25% is too large for > Cu?  > > Also I will try to dope with lower percent too. > > And what things I should pay attention to, any advice? Thanks! > > Regards > > Yao-Hong Huang > > -- > > Graduate student > > Department of Mechanical Engineering > > National Cheng Kung University > > Tainan, Taiwan ******************************************************** - 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), Italy Tel + 39 06 90672836 - Fax +39 06 90672316 E-mail: <[email protected]> http://www.ism.cnr.it/en/staff/giuseppe-mattioli/ ResearcherID: F-6308-2012 _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
