Dear Saad I used your suggestion but unfortunately a is about 4.2 angstrom was achieved. I relaxed it to zero pressure and minimum energy. I do not know how to do !!!!!!!!!
Thanks On 3/12/15, saad sarwar <[email protected]> wrote: > you should use > Ba_lda_v1.uspp.F.UPF > Ti_lda_v1.uspp.F.UPFO_lda_v1.2.uspp.F.UPF > > > On Thursday, March 12, 2015 9:45 PM, Mojtaba Mirseraji > <[email protected]> wrote: > > > Dear Paolo and all users > > I want to relax the structures of tetragonal and cubic BaTiO3 (barium > titanate) > But when I use some pseudopotentials, I can not reach the correct > lattice parameters. > Unfortunately, I calculate a=4.100 to 4.200 for cubic structure of > BaTiO3 but all articles reported that "a" is about 4.006 and my > results are very different !!!!!!!!!!!!!! > Also, for tetragonal structure a=3.800 to 3.900 and c/a=1.250 to 1.265 > !!!!!!!!!!!!!! > but this is reported in some articles, a=3.991 and c/a=1.011 > !!!!!!!!!!!!!!! > > I used some pseudopotentials such as pz (for PSLibrary, both rrkjus > and kjpaw), pw91 (for PSLibrary, both rrkjus and kjpaw), relpw91 (for > PSLibrary, both rrkjus and kjpaw), pw91 (for Vanderbilt, US) and .... > !!!!!!!!!!!!! > All these did not calculate correctly both lattice parameters and > polarizations, unfortunately !!!!!!!!!!! > > Which pseudopotential is good for this job? give me some suggestions, please > !!! > In general, I am very disappointed to QE and pseudopotentials > > Thanks in advance > > Mojtaba Mirseraji > Ph.D. Candidate, theoretical condensed matter physics > Arak Univ. > I.R.IRAN > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum > > > _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
