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<div class="moz-cite-prefix">On 05/14/2013 10:49 PM, Jennifer
Wohlwend wrote:<br>
</div>
<blockquote cite="mid:BLU164-W162365B2D17E92945E09CAA2A10@phx.gbl"
type="cite">
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<div dir="ltr">Thank you for your reply, I guess I thought that,
for metals, the printed Ef was accurate and was not simply an
absolute energy.<br>
</div>
</blockquote>
<br>
It is totally accurate, but it is only meaningful with respect to
the occupied bands structure.<br>
<br>
If you want to estimate the position of Ef with respect to the
vacuum, i.e. the energy required to pull out an electron from the
metal a.k.a. work-function, you first need to define what "out" is,
which is non-trivial in periodic boundary conditions.<br>
<br>
This problem is tackled in the WorkFct example, in PP/examples:<br>
WorkFct_example:<br>
This example shows how to use pw.x, pp.x, and average.x to<br>
compute the work function of a metal using the slab-supercell<br>
approximation. This example is of a 4 layer unrelaxed Al(100)
slab<br>
with 5 equivalent layers of vacuum between the surfaces.<br>
<br>
good work<br>
<br>
<pre class="moz-signature" cols="72">--
Dr. Lorenzo Paulatto
IdR @ IMPMC -- CNRS & Université Paris 6
phone:+33 (0)1 44275 084 / skype: paulatz
www: <a class="moz-txt-link-freetext" href="http://www-int.impmc.upmc.fr/~paulatto/">http://www-int.impmc.upmc.fr/~paulatto/</a>
mail: 23-24/4é16 Boîte courrier 115, 4 place Jussieu 75252 Paris Cédex 5</pre>
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