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<p>Dear Giuseppe,</p>
<p><br>
</p>
<p>Thanks very much for the hint. </p>
<p><br>
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<p>Regards,</p>
<p><br>
</p>
<p>Amin </p>
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<div id="x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> pw_forum-bounces@pwscf.org <pw_forum-bounces@pwscf.org> on behalf of Giuseppe Mattioli <giuseppe.mattioli@ism.cnr.it><br>
<b>Sent:</b> Tuesday, February 20, 2018 10:22:14 AM<br>
<b>To:</b> PWSCF Forum<br>
<b>Subject:</b> Re: [Pw_forum] Excitation of inorganic materials</font>
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Dear Amin<br>
I'm not an expert of excitations in periodic systems, but this paper<br>
<br>
J. Chem. Phys. 129, 034101 (2008)<br>
<br>
suggests that meaningful results can be obtained in periodic systems <br>
(as well as in charge-transfer isolated systems) by applying TDDFT <br>
with EXX kernels. AFAIK such EXX kernels are implemented in TDDFPT, <br>
but they are likely very expensive. Moreover, I do not know if speedup <br>
tricks such as ecutfock and ACE have been implemented yet.<br>
HTH<br>
Giuseppe<br>
<br>
Quoting Amin Mirzai <amin.mirzai@mek.lth.se>:<br>
<br>
> Dear QE users and developers,<br>
><br>
><br>
> I was wondering if you could elaborate on possibility of modeling <br>
> absorption spectra of inorganic materials/molecules using TDDFPT <br>
> module of QE. There are many discussion regarding insufficiency of <br>
> TDDFT itself to model charge transfer and corresponding issues with <br>
> excitation. on top of that, when I went through excitation papers I <br>
> have found out, most excitation papers are done on organic molecules <br>
> such as methane and etc. This is also true in case of QE TDDFPT <br>
> examples.<br>
><br>
> Hence, is it possible to model absorption spectra of complex <br>
> inorganic molecule such as Y2SiO5 with TDDFPT module or in the <br>
> larger context TDDFT itself?<br>
><br>
><br>
> Thanks in advance,<br>
><br>
> With kind regards,<br>
><br>
><br>
> Amin Mirzai<br>
><br>
> PhD candidate<br>
><br>
> Division of Mechanics<br>
><br>
> Lund University<br>
<br>
<br>
<br>
GIUSEPPE MATTIOLI<br>
CNR - ISTITUTO DI STRUTTURA DELLA MATERIA<br>
Via Salaria Km 29,300 - C.P. 10<br>
I-00015 - Monterotondo Scalo (RM)<br>
Mob (*preferred*) +39 373 7305625<br>
Tel + 39 06 90672342 - Fax +39 06 90672316<br>
E-mail: <giuseppe.mattioli@ism.cnr.it><br>
<br>
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