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<div class="moz-cite-prefix">Dear Evan,<br>
<br>
On 31/10/2016 08:51, evan wrote:<br>
</div>
<blockquote
cite="mid:425b34e.8bd0.15819b9182b.Coremail.ewan26@126.com"
type="cite">
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style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial">
<p class="MsoNormal" align="left"><span style="font-size: 12pt;
font-family: Cambria, serif;" lang="EN-US">Dear Stefano </span><span
style="font-size: 12pt; font-family: 宋体;" lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal" align="left"><span style="font-size: 12pt;
font-family: Cambria, serif;" lang="EN-US">Thank you for
your
reply, but I do not understand what’s you meaning in the
last letter. <o:p></o:p></span></p>
<p class="MsoNormal" align="left"><span style="font-size: 12pt;
font-family: Cambria, serif;" lang="EN-US">What I want to
know
is that when the lattice structure of GaAs (fcc) is
different from the simulation
cell (sc, ibrav =1 in my calculations), the coordinates of
high symmetry points
in Brillioun zone of which lattice structure (fcc or those
of sc) I should specify
in the PWscf input file?<o:p></o:p></span></p>
<p class="MsoNormal" align="left"><span style="font-size: 12pt;
font-family: Cambria, serif;" lang="EN-US">I am not familiar
with this issue, but it is important for my study. Thank you
for your patience.</span></p>
</div>
</blockquote>
<br>
then I would suggest that you get familiar with the concepts of real
and reciprocal space, supercells and refolding of points in the
Brillouin zone.<br>
In your calculation 16 valence bands are computed. Did you wonder
why and what they are ? <br>
The coordinates of the X point are not your problem.<br>
<br>
regards,<br>
<br>
stefano<br>
---<br>
On two occasions I have been asked [by members of Parliament!],
"Pray, Mr.<br>
Babbage, if you put into the machine wrong figures, will the right
answers<br>
come out?" I am not able rightly to apprehend the kind of confusion
of<br>
ideas that could provoke such a question.<br>
-- Charles Babbage<br>
<br>
<br>
<blockquote
cite="mid:425b34e.8bd0.15819b9182b.Coremail.ewan26@126.com"
type="cite">
<div
style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial">
<p class="MsoNormal" align="left"><span style="font-size: 12pt;
font-family: 宋体;" lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal" align="left"><span style="font-size: 12pt;
font-family: Cambria, serif;" lang="EN-US">Regards</span><span
style="font-size: 12pt; font-family: 宋体;" lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal" align="left"><span style="font-size: 12pt;
font-family: Cambria, serif;" lang="EN-US">Evan</span><span
style="font-size: 12pt; font-family: 宋体;" lang="EN-US"><o:p></o:p></span></p>
<span style="font-size: 12pt; font-family: Cambria, serif;"
lang="EN-US">USC,
China</span><br>
<br>
<br>
<br>
<br>
<br>
At 2016-10-31 14:32:53, "Stefano de Gironcoli"
<a class="moz-txt-link-rfc2396E" href="mailto:degironc@sissa.it"><degironc@sissa.it></a> wrote:<br>
<blockquote id="isReplyContent" style="PADDING-LEFT: 1ex;
MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">
<div>The one you are using: ibrav=1.</div>
<div id="AppleMailSignature">Do not expect to see a band
structure similar to the usual one tho</div>
<div id="AppleMailSignature"><br>
stefano
<div>(sent from my phone)</div>
</div>
<div><br>
On 31 Oct 2016, at 03:03, evan <<a moz-do-not-send="true"
href="mailto:ewan26@126.com">ewan26@126.com</a>> wrote:<br>
<br>
</div>
<blockquote type="cite">
<div>
<div
style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial">
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria","serif";mso-ascii-theme-font:major-latin;mso-hansi-theme-font:major-latin"
lang="EN-US">Dear Stefano
and </span><span
style="font-size:12.0pt;font-family:"Cambria","serif";mso-ascii-theme-font:major-latin;mso-hansi-theme-font:major-latin;mso-bidi-font-family:
Arial" lang="EN-US">Andrew</span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria","serif";mso-ascii-theme-font:major-latin;mso-hansi-theme-font:major-latin"
lang="EN-US">Thank you
for your kind replies. Let me ask a more general
question which I think about.<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria","serif";mso-ascii-theme-font:major-latin;mso-hansi-theme-font:major-latin"
lang="EN-US"> </span><span style="font-size: 12pt;
font-family: Cambria, serif;" lang="EN-US">I want to
calculate the band structure of GaAs (FCC structure)
in a simple cubic lattice
cell with eight atoms (ibrav =1). If I specify the k
points </span><span style="font-size: 12pt;
font-family: Cambria, serif;" lang="EN-US">in
units of 2pi/a (K_POINTS tpiba_b), </span><span
style="font-size: 12pt; font-family: Cambria,
serif;" lang="EN-US">the high symmetry points in
Brillioun zone of
which cell I should specify in the input file, FCC
(ibrav =2) or those of SC (ibrav=1)
lattice structure?</span></p>
<p class="MsoNormal"><span style="font-size: 12pt;
font-family: Cambria, serif;" lang="EN-US">If I
specify
the k points in in <span style="color:red">crystal
coordinates</span> </span><span style="font-size:
12pt; font-family: Cambria, serif;" lang="EN-US">(K_POINTS
crystal_b), then of </span><span style="font-size:
12pt; font-family: Cambria, serif;" lang="EN-US">which
cell I should specify the k points in the input
files, FCC or SC lattice structure.</span></p>
<p class="MsoNormal"><span style="font-family: Cambria,
serif; font-size: 12pt; line-height: 1.7;">Thank you
in
advance.</span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria","serif";mso-ascii-theme-font:major-latin;mso-hansi-theme-font:major-latin"
lang="EN-US">Regards<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria","serif";mso-ascii-theme-font:major-latin;mso-hansi-theme-font:major-latin"
lang="EN-US">Evan<o:p></o:p></span></p>
<p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Cambria","serif";mso-ascii-theme-font:major-latin;mso-hansi-theme-font:major-latin"
lang="EN-US">USC, China<o:p></o:p></span></p>
<br>
At 2016-10-30 02:17:33, "stefano de gironcoli" <<a
moz-do-not-send="true" href="mailto:degironc@sissa.it">degironc@sissa.it</a>>
wrote:<br>
<blockquote id="isReplyContent" style="PADDING-LEFT:
1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px
solid">
<div class="moz-cite-prefix">Dear Evan,<br>
GaAS structure is zincblend (2 atoms per cell).
its X point is indeed 2pi/a(1,0,0).<br>
if you choose to compute GaAs in a SC cell (8
atoms pr cell) then that point is indeed equivalent
to Gamma. The zone boundary of the SC cell is
pi/a(1,0,0) but this of course does not correspond
to the X point of the zincblend structure.<br>
HTH<br>
stefano<br>
<br>
On 29/10/2016 16:00, evan wrote:<br>
</div>
<blockquote
cite="mid:722d3f29.2f72.15810bde114.Coremail.ewan26@126.com"
type="cite">
<div
style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial">
<div id="isForwardContent">
<div
style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial">
<p class="MsoNormal" style="line-height: 12pt;
background-image: initial;
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initial; background-clip: initial;
background-position: initial;
background-repeat: initial;" align="left"><span
style="font-size: 12pt; font-family:
Cambria, serif;" lang="EN-US">Hello,
everyone<o:p></o:p></span></p>
<p class="MsoNormal"
style="line-height:12.0pt"><span
style="font-size: 12pt; font-family:
Cambria, serif; background-image: initial;
background-attachment: initial;
background-size: initial;
background-origin: initial;
background-clip: initial;
background-position: initial;
background-repeat: initial;" lang="EN-US">I
calculated the band structure of GaAs in a
simple cubic lattice cell (ibrav=1), I
searched from the internet the coordinates
of X-point in the first Brillouin zone are
2pi/a(0,0,1) or 2pi/a(1,0,0), but both
results show that band gap occurs at G and
X points simultaneously, it seems to me
that the X is equivalent to G, can you
tell me the correct X point coordinates
which give me the reasonable result. </span><span
style="font-size: 12pt; font-family:
Cambria, serif;" lang="EN-US">The input
files and results are attached, you can
show what is wrong in the input file.</span><span
style="font-size: 12pt; font-family:
Cambria, serif; background-image: initial;
background-attachment: initial;
background-size: initial;
background-origin: initial;
background-clip: initial;
background-position: initial;
background-repeat: initial;" lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: 12pt;
background-image: initial;
background-attachment: initial;
background-size: initial; background-origin:
initial; background-clip: initial;
background-position: initial;
background-repeat: initial;" align="left"><span
style="font-size: 12pt; font-family:
Cambria, serif;" lang="EN-US">Your
suggestions are appreciated.<o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: 12pt;
background-image: initial;
background-attachment: initial;
background-size: initial; background-origin:
initial; background-clip: initial;
background-position: initial;
background-repeat: initial;" align="left"><span
style="font-size: 12pt; font-family:
Cambria, serif;" lang="EN-US">Yours
sincerely<o:p></o:p></span></p>
<p class="MsoNormal" style="line-height: 12pt;
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initial; background-clip: initial;
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style="font-size: 12pt; font-family:
Cambria, serif;" lang="EN-US">Evan<o:p></o:p></span></p>
<p class="MsoNormal"> </p>
<p class="MsoNormal" style="line-height: 12pt;
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initial; background-clip: initial;
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background-repeat: initial;" align="left"><span
style="font-size: 12pt; font-family:
Cambria, serif;" lang="EN-US">USC, China</span><span
style="font-size: 12pt; font-family:
Cambria, serif;" lang="EN-US"> </span><span
style="font-family: Arial, sans-serif;"
lang="EN-US"><o:p></o:p></span></p>
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