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Dear Eduardo,</div>
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<div>thanks for your consideration on my problem,</div>
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<div>Bests.</div>
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<div>Yavar</div>
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<blockquote style="border-left: #000000 2px solid; padding-left: 5px;
padding-right: 0px; margin-left: 5px; margin-right: 0px">-----Original
Message-----<br />
From: Eduardo Ariel Menendez Proupin <eariel99@gmail.com><br />
To: pw_forum@pwscf.org<br />
Date: Mon, 9 Jul 2012 09:44:20 +0200<br />
Subject: Re: [Pw_forum] HOMO,LUMO isosurface, USPP or NCPP?<br />
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Dear Yavar<br />
<br />
USPP and NCPP are mathematical methods to approximate the solution of the
same physical problem. Hence, there must be no physically different results,
unless one of the pseudopotentials is faulty. Both types of pseudopotentials
have cutoff radii, which are larger for NCPP than for USPP. The
wavefunctions computed with any pseudopotential should be equal to the
all-electron wavefunctions in the spatial region outside the spheres
centered at each atom with spheres radii equal to the cutoff radii of the
corresponding pseudopotential. Inside any sphere, the wavefunctions are
different and are meaningless. To have the correct wavefunctions inside the
spheres you have any of the following options a) all-electron calculations
(with a different code,e.g. ADF, Gaussian, LMTO, etc), b) use a PP with a
smaller cutoff radius (and larger ecutrho and ecutwfc), c) use PAW
(projector augmented wave). <br />
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sincerely yours<br />
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Eduardo Menendez Proupin
<div>Departamento de Química Fisica Aplicada<br />
Facultad de Ciencias<br />
Universidad Autónoma de Madrid<br />
28049 Madrid, Spain<br />
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<div>Phone: <a target="_blank" value="+34914976706"
href="tel:%2B34%2091%20497%206706">+34 91 497 6706</a></div>
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<div class="gmail_quote"><blockquote class="gmail_quote" style="border-left:
#ccc 1px solid; margin: 0px 0px 0px 0.8ex; padding-left: 1ex">
<div>Dear QE users.</div>
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<div>I want to plot HOMO, LUMO isosurfaces. what is the
physical origin of difference between results from choosing USPP
with NCPP?</div>
<div> Thanks in advance.<br />
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-------------------------------------------<br />
Yavar Taghipour Azar<br />
PhD Student<br />
Physics Group, AEOI<br />
Tehran-Iran<br />
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Email: <a>ytaghipour@aeoi.org.ir</a><br />
Phone: <a target="_blank" value="+982182064556"
href="tel:%2B98%20%280%29%2021%2082064556">+98 (0) 21 82064556</a><br />
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