<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> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%<div dir="ltr">%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%<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></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><br></div></div></div><div style="margin-left:40px;text-align:left"><div style="text-align:right"><div style="text-align:left">Any help will be appreciated. thank you in advance<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.</div></div></div></div>
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