<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Dear Giuseppe,<div><br></div><div> is there any concrete evidence that "ab initio" van der Waals vdW-DF is systematically better than Grimme's vdW?</div><div>Are you aware of any paper comparing the latest version of the two methodologies (or "phisolophies", if you want), i.e. vdW-DF2 vs DFT-D3?</div><div><br></div><div>Cheers,</div><div><br></div><div>GS</div><div><br></div><div><br><div><div>Il giorno 23/mar/2011, alle ore 10.12, <a href="mailto:giuseppe.mattioli@mlib.ism.cnr.it">giuseppe.mattioli@mlib.ism.cnr.it</a> ha scritto:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div><br>Dear all<br>You can do better than the semiempirical "Grimme" correction. There is<br>a new ab initio van der Waals correlation functional implemented in QE<br>4.3a. Try input_dft='vdW-DF', in the &sysytem list.<br>By the way, what about a (semiempirical or ab initio) vdW scheme in<br>cp.x? Is there any project going on?<br><br>Yours<br><br>Giuseppe<br><br>Quoting Masoud Nahali <<a href="mailto:masoudnahali@gmail.com">masoudnahali@gmail.com</a>>:<br><br><blockquote type="cite">Dear Eric<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">Try london="true" to get improved answer; as you should know DFT is weak<br></blockquote><blockquote type="cite">to calculate dispersion forces and by using the keyword one can include<br></blockquote><blockquote type="cite">these forces semi-empirically. I hope it helps.<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">Best Wishes<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"> Masoud<br></blockquote><blockquote type="cite">--------------<br></blockquote><blockquote type="cite">Masoud Nahali, Sharif University of Technology<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">Eric Wrote:<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">Dear all,<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">I'm trying to optimize unit cell parameter of graphite.<br></blockquote><blockquote type="cite">The problem is the c axis gets too long.<br></blockquote><blockquote type="cite">Starting from published data my initial parameters are a=4.59203 Bohr<br></blockquote><blockquote type="cite">and c=12.513 Bohr.<br></blockquote><blockquote type="cite">The final values are 4.664 and 15.829 respectively.<br></blockquote><blockquote type="cite">I need someone to explain to me what I did wrong, I've attached my input<br></blockquote><blockquote type="cite">file.<br></blockquote><blockquote type="cite">That's a basic calculation so it's very frustrating to not make it done.<br></blockquote><blockquote type="cite">I thank you in advance,<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite"> Eric.<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">--<br></blockquote><blockquote type="cite">/Be the change you wish to see in the world<br></blockquote><blockquote type="cite">/ --- Mahatma Gandhi ---<br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">Dr. Éric Germaneau <mailto:germaneau at <a href="http://gucas.ac.cn">gucas.ac.cn</a><br></blockquote><blockquote type="cite"><<a href="http://www.democritos.it/mailman/listinfo/pw_forum">http://www.democritos.it/mailman/listinfo/pw_forum</a>>><br></blockquote><blockquote type="cite"><br></blockquote><blockquote type="cite">College of Physical Sciences<br></blockquote><blockquote type="cite">Graduate University of Chinese Academy of Sciences<br></blockquote><blockquote type="cite">Yuquan Road 19A<br></blockquote><blockquote type="cite">Beijing 100049<br></blockquote><blockquote type="cite">China<br></blockquote><blockquote type="cite"><br></blockquote><br>Giuseppe Mattioli<br>ISM-CNR<br>Italy<br><br><br><br><br>_______________________________________________<br>Pw_forum mailing list<br><a href="mailto:Pw_forum@pwscf.org">Pw_forum@pwscf.org</a><br>http://www.democritos.it/mailman/listinfo/pw_forum<br></div></blockquote></div><br><div>
<span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: medium; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div><span class="Apple-style-span" style="color: rgb(126, 126, 126); font-size: 16px; font-style: italic; "><br class="Apple-interchange-newline">§ Gabriele Sclauzero, EPFL SB ITP CSEA</span></div><div><font class="Apple-style-span" color="#7E7E7E"><i> PH H2 462, Station 3, CH-1015 Lausanne</i></font></div></span>
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