You've listed the Wyckoff positions of the atoms, which generate all of the atoms in the unit cell. The space group for MoO3 is #62. Those points are (4c) Wyckoff positions, which means that there are 16 atoms in the unit cell.
There are two ways to handle this: 1) Investigate the crystal_sg option for ATOMIC_POSITIONS 2) Use the space group tables to unfold the (4c) sites To do either, you'll need to know which orientation of space group 62 your reference is using: there are 6 possibilities (see http://img.chem.ucl.ac.uk/sgp/large/ortho.htm, and look for 62). The reference you are using should tell you which one it is, or give you some clue by describing nearest neighbor distances. You'll have to do some research. Unfortunately we don't have MoO3 up on the prototype web page yet, so I can't really tell you any more than that. We have some updates coming, and this isn't the first time MoO3 has been mentioned, so I'll try to add it in soon. If you look at the examples in http://www.aflowlib.org/CrystalDatabase/orthorhombic_spacegroup.html under Pnma (#62) you'll see how to convert (x 1/4 z) coordinates to multiple atoms for the Pnma orientation, but be warned that the relationship is different for other orientations. On Thu, Jul 20, 2017 at 3:09 PM, hamed asadi <[email protected]> wrote: > dear all, > I have try to make MoO3 bulk unit cell but the resulted structure is not > like the published one. The input file which I made it from papers: > > > &CONTROL > calculation = 'scf' , > restart_mode = 'from_scratch' , > etot_conv_thr = 1.0E-8 , > forc_conv_thr = 1.0D-8 , > outdir='/home/asa/Desktop/MoO3/out', > pseudo_dir = '/home/asa/Desktop/MoO3/pp', > wf_collect=.true. > tprnfor = .true. > tstress = .true. > verbosity= 'low', > / > &SYSTEM > ibrav = 9, > celldm(1) =7.48501621, > celldm(2) =3.498447323, > celldm(3) =0.932944533, > nbnd = 30, > nat = 4, > ntyp = 2, > ecutwfc = 40 , > ecutrho = 400, > occupations = 'smearing' , > degauss= 0.01 , > smearing= 'gaussian', > > / > &ELECTRONS > mixing_beta = 0.7 > conv_thr = 1.D-8 , > / > &IONS > ion_dynamics= 'bfgs' > > / > &CELL > cell_dynamics = 'bfgs' , > cell_factor = 2 > / > ATOMIC_SPECIES > Mo 95.94 Mo.pbe-spn-rrkjus_psl.0.2.UPF > O 15.999 O.pbe-rrkjus.UPF > ATOMIC_POSITIONS {crystal} > Mo 0.077 0.25 0.501 > O 0.1003 0.25 0.075 > O 0.2242 0.25 0.068 > O 0.4328 0.25 0.443 > K_POINTS {automatic} > 30 30 1 0 0 0 > > > I try ibrave 8 to 11 for this case but anyone does not looks like the > correct structure. Please help me to get the right structure. > Thank you in advance. > H. Asadi > K. N. Toosi university of technology > > -- > This message has been scanned for viruses and dangerous content by > *KNTU Antispam System (E.F.A. Project)* <http://www.efa-project.org>, and > is believed to be clean. > > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum > -- [image: USNA_Gold_Seal.png] Michael J. Mehl, Ph.D. Kinnear Chair in Physics The United States Naval Academy Mail Stop 9C 572 Holloway Road Chauvenet Hall 257 Annapolis MD 21402 (410)293-6685 [email protected] Library of Crystallographic Prototypes <http://aflow.org/CrystalDatabase/>
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