I dont know if this is the problem but the last two oxygens are 4c not 8d stefano (sent from my phone)
> On 19 Nov 2016, at 00:25, John Bilgerman <[email protected]> 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 > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
