<div dir="ltr"><div><div><div>Dear Friends,<br></div>                  I optimised anatase structure with LDA pseudopotential. It upperestimates the lattice parameter values. In literature it is shown that LDA should underestimate lattice parameters upto 1-2%. <br><br></div>Below is my input and final(optimised) values.<br>Input lattice parameters.                   <br> A =  3.785,<br> C =  9.514,<br><br></div>Optimised lattice parameters<br><br>A =  3.902,<br>C =  9.804,<br><br> my input file is as follows. <br><div><br> &CONTROL<br>                       title = 'anatase' ,<br>                      calculation = 'vc-relax' ,<br>                restart_mode = 'from_scratch' ,<br>                  pseudo_dir = '/home/suresh/isha/',<br>                      outdir ='/home/suresh/isha/kriya/',<br>                      prefix = 'anatase',<br>                     tstress = .true. ,<br>                     tprnfor = .true. ,<br>                     <br><br><br>                 <br>                 <br> /<br> &SYSTEM<br>                       ibrav = 6,<br>                           A =  3.785,<br>                           C =  9.514,<br>                         nat = 12,<br>                        ntyp = 2,<br>                     ecutwfc = 110 ,<br>                     ecutrho = 440<br><br><br>                 <br>                    <br>                      <br> /<br> &ELECTRONS<br>conv_thr = 1.D-8<br><br> /<br> &IONS<br><br><br> /<br> &CELL<br>               <br><br>               <br> /<br>ATOMIC_SPECIES<br>   Ti   47.86700  Ti.pz-n-nc.UPF<br>    O   15.99940  O.pz-nc.UPF<br>ATOMIC_POSITIONS (crystal)<br>Ti       0.000000000   0.000000000   0.000000000<br>Ti       0.000000000   0.500000000   0.250000000<br>Ti       0.500000000   0.500000000   0.500000000<br>Ti       0.500000000   0.000000000   0.750000000<br>O        0.000000000   0.000000000   0.206600000<br>O        0.000000000   0.500000000   0.456600000<br>O        0.500000000   0.000000000   0.543400000<br>O        0.500000000   0.500000000   0.293400000<br>O        0.500000000   0.500000000   0.706600000<br>O        0.500000000   0.000000000   0.956600000<br>O        0.000000000   0.500000000   0.043400000<br>O        0.000000000   0.000000000   0.793400000<br>K_POINTS automatic <br>4 4 4  0 0 0<br clear="all"><div><div><div><div><div><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div><div><div style="margin-left:40px;text-align:right">                  <br>With Regards,<br></div><div style="text-align:right">A.Suresh,<br></div></div><div style="text-align:right">Research Scholar,</div></div><div style="text-align:right">Madurai Kamaraj University,<br></div></div><div style="text-align:right">Madurai.<br></div></div></div></div></div></div>
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