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<div class="moz-cite-prefix">Perhaps do a google search for
correlated materials. For example, maybe the following references
are of interest:<br>
<br>
<a class="moz-txt-link-freetext" href="https://en.wikipedia.org/wiki/Strongly_correlated_material#Electronic_structures">https://en.wikipedia.org/wiki/Strongly_correlated_material#Electronic_structures</a><br>
<a class="moz-txt-link-freetext" href="https://arxiv.org/abs/1309.3355v1">https://arxiv.org/abs/1309.3355v1</a> (Section 1. LDA+U vs
Hartree-Fock and Exact Exchange)<br>
<a class="moz-txt-link-freetext" href="http://www.cond-mat.de/events/correl12/manuscripts/">http://www.cond-mat.de/events/correl12/manuscripts/</a> (The LDA+U
Approach: A Simple Hubbard Correction for Correlated Ground
States)<br>
<br>
On 11/22/2016 3:28 AM, Luis Ogando wrote:<br>
</div>
<blockquote
cite="mid:CANpt3shubkrRDGJvtPmbfSxRpjQPm2N8UwF9qNyG9QnLmsAR0g@mail.gmail.com"
type="cite">
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<div> Thank you Pablo !<br>
</div>
I am looking for something introductory like wikipedia.
Do you have some reference "in this direction" ?<br>
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All the best,<br>
</div>
Luis<br>
<br>
<br>
</div>
<div class="gmail_extra"><br>
<div class="gmail_quote">2016-11-21 15:25 GMT-02:00 delamora <span
dir="ltr"><<a moz-do-not-send="true"
href="mailto:delamora@unam.mx" target="_blank">delamora@unam.mx</a>></span>:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
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style="font-size:12pt;color:#000000;font-family:Calibri,Arial,Helvetica,sans-serif"
dir="ltr">
<p>Luis, look for Hubbard Model</p>
<p>NaCl U2</p>
<p> Pablo<br>
</p>
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<hr style="display:inline-block;width:98%">
<div id="m_-1049646723207799152divRplyFwdMsg" dir="ltr"><font
style="font-size:11pt" face="Calibri, sans-serif"
color="#000000"><b>De:</b> Wien <<a
moz-do-not-send="true"
href="mailto:wien-bounces@zeus.theochem.tuwien.ac.at"
target="_blank">wien-bounces@zeus.theochem.<wbr>tuwien.ac.at</a>>
en nombre de Luis Ogando <<a moz-do-not-send="true"
href="mailto:lcodacal@gmail.com" target="_blank">lcodacal@gmail.com</a>><br>
<b>Enviado:</b> lunes, 21 de noviembre de 2016
11:00:23 a. m.<span class=""><br>
<b>Para:</b> A Mailing list for WIEN2k users<br>
<b>Asunto:</b> Re: [Wien] Hartree-Fock and the
Hubbard Model</span></font>
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<div>Dear Prof. Tran,<br>
<br>
</div>
I would like to read more about this subject,
but, unfortunately, your link gave me a message
like : " Wikipedia does not have an article with
this exact name. "<br>
</div>
<div> Please<b>,</b> could you suggest another
non-specialist reference like wikipedia ?<br>
</div>
<div> Thank you,<br>
</div>
<div> Luis<br>
</div>
</div>
<div class="gmail_extra"><br>
<div class="gmail_quote">2016-11-20 13:28
GMT-02:00 <span dir="ltr"><<a
moz-do-not-send="true"
href="mailto:tran@theochem.tuwien.ac.at"
target="_blank">tran@theochem.tuwien.ac.at</a>></span>:<br>
<blockquote class="gmail_quote" style="margin:0
0 0 .8ex;border-left:1px #ccc
solid;padding-left:1ex">
Hi,<br>
<br>
DFT+U is a cheap but rather rough
approximation of HF.<br>
Beside this, there is also the difference that
in DFT+U, the Coulomb<br>
operator is attenuated in order to account for
the screening due to<br>
correlation. In HF, no correlation is
included.<br>
In hybrids, the screening is included by using
only ~25% of HF exchange<br>
(and there is also correlation coming from a
LDA/GGA correlation term).<br>
<br>
Hybrid, onsite-hybrid and DFT+U are more or
less the same,<br>
since all of them are one-electron methods and
mix HF with LDA/GGA.<br>
As Karel said, they are better than LDA/GGA,
but can not reproduce<br>
the experimental observations that are beyond
the one-electron methods.<br>
DMFT is better since it is a beyond
one-electrons method.<br>
<br>
Read that:<br>
<a moz-do-not-send="true"
href="https://en.wikipedia.org/wiki/LDA+U"
rel="noreferrer" target="_blank">https://en.wikipedia.org/wiki/<wbr>LDA+U</a><br>
<br>
FT
<div class="m_-1049646723207799152HOEnZb">
<div class="m_-1049646723207799152h5"><br>
<br>
<blockquote class="gmail_quote"
style="margin:0 0 0 .8ex;border-left:1px
#ccc solid;padding-left:1ex">
On Wed, 16 Nov 2016, delamora wrote:<br>
<br>
<br>
Dear Fabien Tran and Karel Vyborny,<br>
<br>
Thanks for your comments.<br>
<br>
<br>
What I want to know is if the Hartree
Fock exchange is what the Hubbard U is<br>
trying to model<br>
<br>
What I know is that for strong
intraatomic repulsion, 3d and 4f, the
Hubbard<br>
U gives good results, although the U is
a parameter.<br>
<br>
But for intermediate intraatomic
repulsion, 4d, 5d, 5f then more
expensive<br>
methods are needed, such as DMFT<br>
<br>
So, if this is the case that the Hartree
Fock exchange is what the Hubbard U<br>
is trying to model then the hybrid
functionals would do a better job.<br>
<br>
So, my question is; What are the Hubbard
U and DMFT trying to model?<br>
<br>
<br>
Cheers<br>
<br>
Pablo de la Mora</blockquote>
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