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Dear Bahadır,<br>
<br>
the input file seems to be OK. Nevertheless, you always have to test
in the end<br>
that no charge is spilling into the vacuum because the sawtooth
function is<br>
creating an artificial potential minimum. Do this by plotting to
total potential<br>
(pp.x, plot_num=1) for example as 3D data file and using average.x
to average<br>
over the in-plane directions. If charge is spilling the potential is
not linear in the<br>
vacuum region or shows other weird behavior. In this case you have
to reduce<br>
the vacuum region in order to reduce the depth of the artificial
minimum. This<br>
on the other hand can lead (for too large electric fields) to a
vacuum region<br>
which is too small, i.e., leading to interactions between the
repeated slabs.<br>
<br>
The wrong gap you get can be due to anything - your initial input
file was just<br>
wrong. The sawtooth within the slab itself is an unphysical
situation.<br>
<br>
Regards<br>
<br>
Thomas<br>
<br>
<br>
P.S.: You're using an ultrasoft pseudopotential. In such cases
ecutrho needs to<br>
be larger than just 4 times ecutwfc. More like 10 times... Which is
also stated in<br>
the documentation...<br>
<br>
<div class="moz-cite-prefix">On 11/20/2015 03:27 PM, Bahadır
salmankurt wrote:<br>
</div>
<blockquote
cite="mid:CADT9cuswAWJBs=OuCFYHw8r76npOv_C1j-Ye41hu5_CVB5whwA@mail.gmail.com"
type="cite">
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<div dir="ltr"><font face="arial, helvetica, sans-serif">Dear Dr. <span
style="font-size:12.8px;white-space:nowrap">Thomas Brumme,</span></font>
<div><font face="arial, helvetica, sans-serif"><span
style="font-size:12.8px;white-space:nowrap"><br>
</span></font></div>
<div><font face="arial, helvetica, sans-serif"><span
style="font-size:12.8px;white-space:nowrap">Thank you for
clear explanation. </span></font></div>
<div><font face="arial, helvetica, sans-serif"><span
style="font-size:12.8px;white-space:nowrap"><br>
</span></font></div>
<div><font face="arial, helvetica, sans-serif"><span
style="font-size:12.8px;white-space:nowrap">And also I
have changed my input file. now, Is everything ok? </span></font></div>
<div><font face="arial, helvetica, sans-serif"><span
style="font-size:12.8px;white-space:nowrap"><br>
</span></font></div>
<div><font face="arial, helvetica, sans-serif"><span
style="font-size:12.8px;white-space:nowrap">****</span></font></div>
<div><font face="arial, helvetica, sans-serif">
<div style=""><span style="white-space:nowrap"><font
size="1">&control</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> calculation='scf'</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> restart_mode='from_scratch',</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> prefix='As',</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> tstress = .true.</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> tprnfor = .true.</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> pseudo_dir
='/home/hakan/tubitak/espresso-5.2.0/pseudo/',</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1">
outdir='/home/hakan/tubitak/As/efield/out/',</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1">! etot_conv_thr = 1.0E-4,</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1">! forc_conv_thr = 1.0D-3,</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> wf_collect=.true.,</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1">! verbosity='high',</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1">tefield=.true.</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"><b>dipfield=.true.</b></font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> /</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1">&system</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1">nbnd=10,</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> ibrav=0,celldm(1)=1.8897,</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> nat= 2, ntyp=1,</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> ecutwfc =30.0,</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> ecutrho=120,</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"><b> emaxpos=0.95,</b></font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> eopreg=0.10,</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> edir = 3,</font></span></div>
<div style=""><span style="white-space:nowrap"><font
size="1"> </font></span><span
style="font-size:x-small;font-family:arial,sans-serif">eamp
= 0.0105,</span></div>
</font><font face="arial, helvetica, sans-serif">
<div style=""><span style="white-space:nowrap"><font
size="1"> /</font></span></div>
<div style=""><font size="1"><span
style="white-space:nowrap">..</span></font><span
style="white-space:nowrap;font-size:x-small">.</span></div>
<div style=""><font size="1"><span
style="white-space:nowrap"><br>
</span></font></div>
<div style="font-size:12.8px;white-space:nowrap">****</div>
<div style="font-size:12.8px;white-space:nowrap"><br>
</div>
<div style="font-size:12.8px;white-space:nowrap">By the way,
the difference is that , when <span
style="font-size:12.8px">E field was </span><span
style="font-size:12.8px">applied </span><span
style="font-size:12.8px;font-family:arial,sans-serif">under
5.00 V/nm ( eamp = </span><span
style="font-size:12.8px;font-family:arial,sans-serif">0.0097
au) E field</span><span style="font-size:12.8px"> </span><span
style="font-size:12.8px">in prb paper which I shared ,
the band gap became about 0.80 eV. But I find this band
gap under 10.5 V/nm (eamp=0.0205 au) E field ( I have
used new input data). </span></div>
</font></div>
<div class="gmail_extra"><br>
</div>
<div class="gmail_extra">what does the reason such a difference
happen? </div>
<div class="gmail_extra"><br>
</div>
<div class="gmail_extra">Thank you again.. </div>
</div>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Dr. rer. nat. Thomas Brumme
Max Planck Institute for the Structure and Dynamics of Matter
Luruper Chaussee 149
22761 Hamburg
Tel: +49 (0)40 8998 6557
email: <a class="moz-txt-link-abbreviated" href="mailto:Thomas.Brumme@mpsd.mpg.de">Thomas.Brumme@mpsd.mpg.de</a>
</pre>
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