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On 07/21/2010 10:59 AM, Masoud Nahali wrote:
<blockquote
cite="mid:AANLkTiloyAn2kZ4OdhuMsMuH6iPmhezWoGcwYe1YhD30@mail.gmail.com"
type="cite">Dear PWscf Users<br>
<br>
For the graphite bulk, in the output file I see "24 Sym.Ops." but for
the graphite surface (a slab with 10 angstrom vacuum) I see "6
Sym.Ops." . Is this plausible and correct ?<br>
</blockquote>
<br>
The symmetry operations are determined correctly in the code. The
symmetry group that you get for a graphite slab depends on which type
of graphite you consider (i.e. hexagonal or Bernal) and how you build
your slab. If your system has a mirror plane coinciding with z=0
(assuming z to be the stacking direction), then you will get 24
operations for an hexagonal graphite slab and 12 for a Bernal graphite
slab (which is the maximum of the symmetry operations possible for each
of the two systems). <br>
To get more information about the symmetry on the output you can
specify verbosity='high'.<br>
<br>
<br>
HTH<br>
<br>
GS <br>
<br>
<br>
<blockquote
cite="mid:AANLkTiloyAn2kZ4OdhuMsMuH6iPmhezWoGcwYe1YhD30@mail.gmail.com"
type="cite">I appreciate your help.<br>
<br>
Many Thanks<br>
Masoud Nahali<br>
SUT<br>
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</blockquote>
<br>
<br>
<pre class="moz-signature" cols="72">--
Gabriele Sclauzero, EPFL SB ITP CSEA
PH H2 462, Station 3, CH-1015 Lausanne
</pre>
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