<div dir="ltr"><div>Dear All,<br></div>             I have carried out convergence and vc-relaxation for undoped 2*2*1 supercell of anatase.Then I replace one oxygen by one nitrogen and did scf calculation to know the energy and forces due to doped nitrogen. While runing code asks me to include smearing methods as follows.<br>
<br> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<br><div><div><div><div><div dir="ltr"><div><div><div><div style="margin-left:40px;text-align:left">     Error in routine electrons (1):<br>
     charge is wrong: smearing is needed<br><div style="text-align:right">%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%  <br><br><br><br><div style="text-align:left"><span style="color:rgb(204,0,0)">so I include randomly gaussian smearing method with 0.01 width without doing convergence with respect to smearing width  in my input file </span></div>
</div></div><div style="margin-left:40px;text-align:left"><div style="text-align:right"><div style="text-align:left"><br><br> &CONTROL<br>                       title = '1anatase' ,<br>                 calculation = 'scf' ,<br>
                restart_mode = 'from_scratch' ,<br>                      outdir = '/home/slave1/Desktop/n-doped-supercell/' ,<br>                  pseudo_dir = '/home/slave1/Desktop/n-doped-supercell' ,<br>
                      prefix = 'anatase' ,<br>               etot_conv_thr = 1.0d-4 ,<br>               forc_conv_thr = 1.0d-3 ,<br>                     tstress = .true. ,<br>                     tprnfor = .true. ,<br>
 /<br> &SYSTEM<br>                       ibrav = 6,                 <br>                           A = 7.579318 ,<br>                           B = 7.579318 ,<br>                           C = 9.650253 ,<br>                       cosAB = 0 ,<br>
                       cosAC = 0 ,<br>                       cosBC = 0 ,<br>                         nat = 48,<br>                        ntyp = 3,<br>                     ecutwfc = 30 ,<br>                     ecutrho = 300 ,<br>
            exxdiv_treatment = 'none' ,<br>             <span style="background-color:rgb(255,0,0)"> occupations = 'smearing' ,<br>                     degauss = 0.01 ,<br>                    smearing = 'gaussian'<br>
 /</span><br> &ELECTRONS<br>                    conv_thr = 1.0d-10 ,<br>                 mixing_beta = 0.7 ,<br> /<span style="background-color:rgb(204,0,0)"><span style></span></span><br> &IONS<br>                ion_dynamics = 'bfgs' ,<br>
               ion_positions = 'from_input' ,<br>                 phase_space = 'full' ,<br>           pot_extrapolation = 'atomic' ,<br>           wfc_extrapolation = 'none' ,<br>                     upscale = 100.d0 ,<br>
                   bfgs_ndim = 1 ,<br>            trust_radius_max = 0.80 ,<br>            trust_radius_min = 1d-3 ,<br>            trust_radius_ini = 0.5d0 ,<br> /<br> &CELL<br>               cell_dynamics = 'bfgs' ,<br>
                 cell_factor = 1.2 ,<br>                 cell_dofree = 'all' ,<br> /<br>ATOMIC_SPECIES<br>   Ti   47.86700  Ti.pw91-sp-van_ak.UPF <br>    O   15.99940  O.pw91-van_ak.UPF <br>    N   14.00600  N.pw91-van_ak.UPF<br>
ATOMIC_POSITIONS crystal<br>Ti    0.0000000000    0.0000000000    0.0000000000<br>Ti    0.2499985872    0.2499985872    0.4999971721<br>Ti    0.0000000000    0.2499985872    0.249998522<br>Ti    0.2499985872    0.0000000000    0.7499958221<br>
Ti    0.0000000000    0.4999971744    0.0000000000<br>Ti    0.2499985872    0.7499957616    0.4999971721<br>Ti    0.0000000000    0.7499957616    0.249998522<br>Ti    0.2499985872    0.4999971744    0.7499958221<br>Ti    0.4999971744    0.0000000000    0.0000000000<br>
Ti    0.7499957616    0.2499985872    0.4999971721<br>Ti    0.4999971744    0.2499985872    0.249998522<br>Ti    0.7499957616    0.0000000000    0.7499958221<br>Ti    0.4999971744    0.4999971744    0.0000000000<br>Ti    0.7499957616    0.7499957616    0.4999971721<br>
Ti    0.4999971744    0.7499957616    0.249998522<br>Ti    0.7499957616    0.4999971744    0.7499958221<br>O    0.0000000000    0.2499985872    0.0430194597<br>O    0.0000000000    0.0000000000    0.2069790644<br>O    0.2499985872    0.2499985872    0.2930179727<br>
O    0.0000000000    0.2499985872    0.4569776784<br>O    0.2499985872    0.0000000000    0.5430166658<br>O    0.2499985872    0.2499985872    0.7069763714<br>O    0.0000000000    0.0000000000    0.7930152798<br>O    0.2499985872    0.0000000000    0.9569748844<br>
O    0.0000000000    0.7499957616    0.0430194597<br>O    0.0000000000    0.4999971744    0.2069790644<br>O    0.2499985872    0.7499957616    0.2930179727<br>O    0.0000000000    0.7499957616    0.4569776784<br>O    0.2499985872    0.4999971744    0.5430166658<br>
O    0.2499985872    0.7499957616    0.7069763714<br>O    0.0000000000    0.4999971744    0.7930152798<br>O    0.2499985872    0.4999971744    0.9569748844<br>O    0.4999971744    0.2499985872    0.0430194597<br>O    0.4999971744    0.0000000000    0.2069790644<br>
O    0.7499957616    0.2499985872    0.2930179727<br>O    0.4999971744    0.2499985872    0.4569776784<br>O    0.7499957616    0.0000000000    0.5430166658<br>O    0.7499957616    0.2499985872    0.7069763714<br>O    0.4999971744    0.0000000000    0.7930152798<br>
O    0.7499957616    0.0000000000    0.9569748844<br>O    0.4999971744    0.7499957616    0.0430194597<br>O    0.4999971744    0.4999971744    0.2069790644<br>O    0.7499957616    0.7499957616    0.2930179727<br>N    0.4999971744    0.7499957616    0.4569776784<br>
O    0.7499957616    0.4999971744    0.5430166658<br>O    0.7499957616    0.7499957616    0.7069763714<br>O    0.4999971744    0.4999971744    0.7930152798<br>O    0.7499957616    0.4999971744    0.9569748844<br>K_POINTS automatic <br>
  4 4 2   0 0 0 <br></div></div></div><div style="margin-left:40px;text-align:left"><div style="text-align:right"><div style="text-align:left"><br>and my doubts are<br></div></div></div><div style="margin-left:40px;text-align:left">
<div style="text-align:right"><div style="text-align:left">1.)  Should  i do convergence test with respect to smearing methods(gaussian M-V M-P) and with respect to smearing width for N-doped supercell as well as for  pure supercell to compare them?<br>
<br></div></div></div><div style="margin-left:40px;text-align:left"><div style="text-align:right"><div style="text-align:left">2) I did convergence test for anatase unitcell and took ecut and k-point values to supercell exactly as anatase unitcell. Is it correct?<br>
<br>3)How to do convergence test for doped supercell because  one do convergence test for unitcell and take converged values exactly as unitcell to supercell, now third atom comes in the supercell but it is not in the unitcell?.<br>
<br>4) Ti   47.86700  Ti.pw91<span style="color:rgb(204,0,0)">-sp-</span>van_ak.UPF <br>    O   15.99940  O.pw91-van_ak.UPF <br>    N   14.00600  N.pw91-van_ak.UPF<br></div></div></div><div style="margin-left:40px;text-align:left">
<div style="text-align:right"><div style="text-align:left">Is my way of choosing pseudopotential correct? Because Ti atom is produced with scalar relativistic correction other twos or not. And sp semicore states of Ti atom are in valence.<br>
</div></div></div><div style="margin-left:40px;text-align:left"><div style="text-align:right"><div style="text-align:left"><br>                          <br></div></div></div><div style="margin-left:40px;text-align:left">
<div style="text-align:right"><div style="text-align:left"><br></div></div></div><div style="margin-left:40px;text-align:left"><div style="text-align:right">              With Regards,<br></div></div><div style="text-align:right">
A.Suresh,<br></div></div><div style="text-align:right">Project Fellow,<br></div></div><div style="text-align:right">Madurai Kamaraj University,<br></div></div><div style="text-align:right">Madurai.<br></div></div></div>
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