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<p>El 06-08-2019 13:01, Paolo Giannozzi escribió:</p>
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<div dir="ltr">On Tue, Aug 6, 2019 at 8:36 PM MARIA CATERINA CEVALLOS BRENES <<a href="mailto:MARIA.CEVALLOS@ucr.ac.cr">MARIA.CEVALLOS@ucr.ac.cr</a>> wrote:</div>
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<div style="font-size: 10pt; font-family: Verdana,Geneva,sans-serif;">However, I'm still not getting the dimerization expected. </div>
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<div>it's a known problem of DFT in simple GGA form: (almost) no dimerization in polyacetylene. The funny thing is that if you do the calculation with an unconverged k-point grid, you get a decent dimerization, that disappears if you push the convergence of k-points</div>
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<div>Paolo</div>
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<div>Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,<br />Univ. Udine, via delle Scienze 208, 33100 Udine, Italy<br />Phone +39-0432-558216, fax +39-0432-558222<br /><br /></div>
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<div class="pre" style="margin: 0; padding: 0; font-family: monospace">_______________________________________________<br /> Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu/quantum-espresso">www.max-centre.eu/quantum-espresso</a>)<br /> users mailing list <a href="mailto:users@lists.quantum-espresso.org">users@lists.quantum-espresso.org</a><br /> <a href="https://lists.quantum-espresso.org/mailman/listinfo/users">https://lists.quantum-espresso.org/mailman/listinfo/users</a></div>
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<p>Do you recommend to use LDA instead or B3LYP? Which one will give me the most accurate Peierls distortion's band gap and why?</p>
<p>And also which pseudo-potential would you recommend me to use?</p>
<p>Thanks :)</p>
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