<div dir="ltr"><div class="gmail_default" style="font-family:verdana,sans-serif">Dear community,</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">I am unable to obtain the square root energy dependency of the bulk Silicon conduction band DOS, despite using a fine k grid (100x100x100). </div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">I expect the DOS near conduction band edge (below the second conduction band of silicon) has a square root dependence with energy. I plotted out the (DOS)^2 vs energy I obtained here: <a href="http://imgur.com/a/Wu07z">http://imgur.com/a/Wu07z</a></div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">As you can see, (DOS)^2 vs. energy is not linear, meaning DOS is not having a square root dependence with energy. Is this an known problem or am I doing something wrong? Here is the nscf calculation input deck:</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">-------</div><div class="gmail_default" style="font-family:verdana,sans-serif">







<p class="gmail-p1"><span class="gmail-s1"> &control</span></p>
<p class="gmail-p1"><span class="gmail-s1">    prefix='silicon',</span></p>
<p class="gmail-p1"><span class="gmail-s1">    pseudo_dir='../pseudo/'</span></p>
<p class="gmail-p1"><span class="gmail-s1">    outdir = './results',</span></p>
<p class="gmail-p1"><span class="gmail-s1">    tstress=.false.,</span></p>
<p class="gmail-p1"><span class="gmail-s1">    tprnfor=.false.,</span></p>
<p class="gmail-p1"><span class="gmail-s1">    calculation = 'nscf',</span></p>
<p class="gmail-p1"><span class="gmail-s1">    verbosity='high',</span></p>
<p class="gmail-p1"><span class="gmail-s1"> /</span></p>
<p class="gmail-p1"><span class="gmail-s1"> &system</span></p>
<p class="gmail-p1"><span class="gmail-s1">    ibrav=  2, celldm(1) =10.2623466921, nat=  2, ntyp= 1,</span></p>
<p class="gmail-p1"><span class="gmail-s1">    ecutwfc = 30.0, ecutrho=300.0, input_dft='PBE', nbnd = 8,</span></p>
<p class="gmail-p1"><span class="gmail-s1"> /</span></p>
<p class="gmail-p1"><span class="gmail-s1"> &electrons</span></p>
<p class="gmail-p1"><span class="gmail-s1">    diagonalization = 'david',</span></p>
<p class="gmail-p1"><span class="gmail-s1">    conv_thr = 1d-08,</span></p>
<p class="gmail-p1"><span class="gmail-s1">    mixing_mode = 'plain',</span></p>
<p class="gmail-p1"><span class="gmail-s1">    mixing_beta = 0.7,</span></p>
<p class="gmail-p1"><span class="gmail-s1"> /</span></p>
<p class="gmail-p1"><span class="gmail-s1">ATOMIC_SPECIES</span></p>
<p class="gmail-p1"><span class="gmail-s1"> Si  28.086  Si.pbe-n-rrkjus_psl.0.1.UPF</span></p>
<p class="gmail-p1"><span class="gmail-s1">ATOMIC_POSITIONS</span></p>
<p class="gmail-p1"><span class="gmail-s1"> Si 0.00 0.00 0.00</span></p>
<p class="gmail-p1"><span class="gmail-s1"> Si 0.25 0.25 0.25</span></p>
<p class="gmail-p1"><span class="gmail-s1">K_POINTS automatic</span></p>
<p class="gmail-p1"><span class="gmail-s1"> 100 100 100 0 0 0</span></p></div><div class="gmail_default" style="font-family:verdana,sans-serif">-------</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">Thanks!</div><div class="gmail_default" style="font-family:verdana,sans-serif"><br></div><div class="gmail_default" style="font-family:verdana,sans-serif">Xufeng</div></div>