<div dir="ltr"><div>Dear QE experts,<br><br></div>I have simulated NFO structure as it is shown in the input file bellow, however after a few bfgs cycle (~2 or 3) my scf iteration reaches limit. I don't understand what might be wrong. I have changed subroutine in cell_base.f90 for 'z' direction like this:<br>-----------------------------------<br> CASE ('z')<br> iforceh = 0<br> iforceh(1,3) = 1<br> iforceh(2,3) = 1<br> iforceh(3,3) = 1<br clear="all"><div><div>------------------------------------</div><div><br></div><div>This change is to leave the system to relax only in 'z' direction. <br></div><div><br></div><div>So could anyone tell me what may go wrong in this case? My pseudopotentials are from pslibrary as well and they have worked for other cases. I want to keep fixed positions of Fe in octahedrally oriented sites cause I must compare with the case of other structure arragements, that's why I kept their position fixed. I'm using "Intel Harwell" processors with 24 cores in google cloud computing system in case this might be adressed as important information.<br></div><div><br></div><div>input file:</div><div>--------------------------------------------------------------------------------------------</div><div> &CONTROL<br> calculation = 'vc-relax' ,<br> restart_mode = 'from_scratch' ,<br> outdir = '/home/drumsris/Bulk-74/' ,<br> pseudo_dir = '/home/drumsris/Bulk-227/' ,<br> prefix = 'nfo' ,<br> tstress = .true. ,<br> tprnfor = .true. ,<br> lorbm = .false.,<br> wf_collect = .false.,<br> /<br> &SYSTEM<br> ibrav = 11,<br> nosym = .true.<br> celldm(1) = 11.2679,<br> celldm(2) = 1.0,<br> celldm(3) = 1.0,<br> space_group = 74,<br> !nbnd = 100 ,<br> nat = 5,<br> ntyp = 4,<br> ecutwfc = 71 ,<br> ecutrho = 564 ,<br> use_all_frac = .true. ,<br> input_dft = 'pbe' ,<br> occupations = 'smearing' ,<br> degauss = 0.0002 ,<br> smearing = 'methfessel-paxton' ,<br> nspin = 2 ,<br> !noncolin = .true., <br> !lspinorb = .true.,<br> starting_magnetization(1) = 1,<br> starting_magnetization(2) = -1,<br> starting_magnetization(3) = 1,<br> starting_magnetization(4) = 0,<br> !tot_magnetization = -1,<br> /<br> &ELECTRONS<br> electron_maxstep = 100,<br> diagonalization = 'david' ,<br> diago_thr_init = 1.0e-5 ,<br> mixing_beta = 0.6,<br> /<br> &IONS<br> ion_dynamics = 'bfgs' ,<br> pot_extrapolation = 'atomic' ,<br> upscale = 10D0 ,<br> bfgs_ndim = 1 ,<br> trust_radius_max = 0.8D0 ,<br> trust_radius_min = 1.D-3 ,<br> trust_radius_ini = 0.5D0 ,<br> w_1 = 0.01D0 ,<br> w_2 = 0.5D0 <br> /<br> &CELL<br> cell_dynamics = 'bfgs' ,<br> press = 0.D0 ,<br> cell_factor = 4.0 ,<br> press_conv_thr = 0.5D0 ,<br> cell_dofree = 'z' , <br>/<br>ATOMIC_SPECIES<br> Ni 58.69000 Ni.pbe-n-kjpaw_psl.1.0.0.UPF <br> Fe1 55.85000 Fe.pbe-n-kjpaw_psl.1.0.0.UPF <br> Fe2 55.85000 Fe.pbe-n-kjpaw_psl.1.0.0.UPF <br> O 16.00000 O.pbe-n-kjpaw_psl.1.0.0.UPF <br>ATOMIC_POSITIONS crystal_sg<br>Fe2 0 0 0.5 <br>Fe1 0 0.2500 0.125 0 0 0<br>Ni 0.25 0.25 0.75 <br>O 0 0.00845 0.73971<br>O 0.23527 0.25000 0.50252<br>K_POINTS {automatic}<br> 5 5 5 0 0 0</div><div>--------------------------------------------------------------------------------------------<br></div><div>Best Regards,</div><div><br></div><div>Ricardo.<br></div><div><br></div><div>-- <br><div class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div><div>Ricardo Afonso<br></div>Student of Magnetism and Superconductivity Group<br></div><div>Federal University of Sao Carlos<br></div></div></div></div></div></div>
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