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<div class="moz-cite-prefix">what the symmetrization does is not an
average.<br>
it is the projection on the totally symmetric group representation
for tensorr of the given rank.<br>
It is used to reconstruct the contribution from the symmetry
equivalent kpoints that are eliminated when the symmetry is
identified.<br>
<br>
stefano<br>
<br>
On 10/01/2012 04:56 AM, Caloma Trumica wrote:<br>
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cite="mid:CAM0egYa6HOVbb3hLF7JomcW4h-4DVJy0Kv9Vu=nyFzqovm1kGw@mail.gmail.com"
type="cite">
<pre wrap="">Dear all,
I have a general question about the symmetry in the Quantum espresso
program.
For quantities such as the Hellmann-Feynman forces and the stress tensor,
why do we need to divide they by the total number of symmetry operations.
Dose it mean that any quantity reported in an electronic structure code is
an average value?
Thank you.
Andy Lau
Hong Kong
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