I made a quick test with USPP's. The unit cell shrinks about 10%. Paolo
On Tue, Nov 22, 2016 at 4:56 PM, John Bilgerman <bilgermanj...@gmail.com> wrote: > Thanks for the tip. I'd only tried up to about a hundred in my tests, I'll > start looking even higher. I attempted this over the weekend on my (old!) > desktop, but found I will have to wait a week or two until I get cluster > access before I can check and see if it was the only issue. > > Thanks, > John > > On Sat, Nov 19, 2016 at 2:34 AM, Paolo Giannozzi <p.gianno...@gmail.com> > wrote: > >> Not sure this is the (only) problem, but 35 Ry for norm-conserving Iron >> with semicore states is way too small. 200-300 Ry is a more appropriate >> cutoff. >> >> Paolo >> >> On Sat, Nov 19, 2016 at 12:25 AM, John Bilgerman <bilgermanj...@gmail.com >> > wrote: >> >>> Hi, >>> >>> I've been banging my head against this and cannot find what is likely a >>> silly mistake despite many tests and lots of reading. >>> >>> I'm trying to optimize the (known) structure of NaFePO4 as a test. I'm >>> starting from the experimental crystal structure, so the drastic collapse >>> of the unit cell to < 1/2 suggests an issue. >>> >>> I know the common problem is inputing the structure wrong, but I've done >>> my best (and sanity-checked the input/output files with Xcrysden). >>> >>> I'm new to QE, any help would be appreciated. >>> >>> Input file: >>> &CONTROL >>> calculation = 'vc-relax' , >>> restart_mode = 'from_scratch' , >>> outdir = './' , >>> wfcdir = './scratch' , >>> pseudo_dir = './pseudo' , >>> disk_io = 'default' , >>> verbosity = 'high' , >>> / >>> &SYSTEM >>> ibrav = 8, >>> space_group = 62 , >>> A = 9.001 , >>> B = 6.874 , >>> C = 5.052 , >>> cosAB = 0 , >>> cosAC = 0 , >>> cosBC = 0 , >>> nat = 6, >>> ntyp = 4, >>> ecutwfc = 35 , >>> ecutrho = 140 , >>> occupations = 'smearing' , >>> degauss = 0.02 , >>> smearing = 'gaussian' , >>> nspin = 2 , >>> starting_magnetization(1) = 0.7, >>> starting_magnetization(2) = 0, >>> starting_magnetization(3) = 0, >>> starting_magnetization(4) = 0, >>> noncolin = .false. , >>> / >>> &ELECTRONS >>> diagonalization = 'david' , >>> / >>> &IONS >>> / >>> &CELL >>> / >>> ATOMIC_SPECIES >>> Fe 55.00000 Fe.pbe-sp-hgh.upf >>> P 30.00000 P.pbe-hgh.upf >>> Na 22.00000 Na.pbe-sp-hgh.upf >>> O 16.00000 O.pbe-hgh.upf >>> ATOMIC_POSITIONS crystal_sg >>> Fe 4a >>> P 4c 0.17585 0.46447 >>> Na 4c 0.34999 0.9702 >>> O 8d 0.1212 0.0682 0.3177 >>> O 8d 0.3486 0.25 0.4561 >>> O 8d 0.1154 0.25 0.7507 >>> K_POINTS automatic >>> 2 3 4 1 1 1 >>> >>> >>> The relevant parts of the CIF file for the structure are: >>> ... >>> _cell_length_a 9.001(8) >>> _cell_length_b 6.874(3) >>> _cell_length_c 5.052(4) >>> _cell_angle_alpha 90. >>> _cell_angle_beta 90. >>> _cell_angle_gamma 90. >>> _cell_volume 312.58 >>> _cell_formula_units_Z 4 >>> _symmetry_space_group_name_H-M 'P n m a' >>> _symmetry_Int_Tables_number 62 >>> ... >>> Fe1 Fe2+ 4 a 0 0 0 . 1. 0 >>> P1 P5+ 4 c 0.17585(4) 0.25 0.46447(8) . 1. 0 >>> Na1 Na1+ 4 c 0.34999(9) 0.25 0.9702(2) . 1. 0 >>> O1 O2- 8 d 0.1212(1) 0.0682(1) 0.3177(2) . 1. 0 >>> O2 O2- 4 c 0.3486(1) 0.25 0.4561(2) . 1. 0 >>> O3 O2- 4 c 0.1154(1) 0.25 0.7507(2) . 1. 0 >>> ... >>> >>> John >>> >>> _______________________________________________ >>> Pw_forum mailing list >>> Pw_forum@pwscf.org >>> http://pwscf.org/mailman/listinfo/pw_forum >>> >> >> >> >> -- >> 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 >> Pw_forum@pwscf.org >> http://pwscf.org/mailman/listinfo/pw_forum >> > > > _______________________________________________ > Pw_forum mailing list > Pw_forum@pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -- 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 Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum