From owner-chemistry@ccl.net Fri May 17 00:24:00 2013 From: "Klemens Noga knoga#chemia.uj.edu.pl" To: CCL Subject: CCL:G: b3lyp* Message-Id: <-48710-130516182412-6229-dQzLCgldDzoBooaMiet3ug : server.ccl.net> X-Original-From: "Klemens Noga" Content-Transfer-Encoding: 8bit Content-Type: text/plain;charset=iso-8859-2 Date: Fri, 17 May 2013 00:24:03 +0200 MIME-Version: 1.0 Sent to CCL by: "Klemens Noga" [knoga#%#chemia.uj.edu.pl] On 16 May 2013, at 17:44, "kalyan onekalyan,yahoo.com" wrote: > http://www.gaussian.com/g_tech/g_ur/k_dft.htm > This is quite good guidline > also you can follow this Linki below > http://www.thch.uni-bonn.de/tc/index.php?section=downloads&subsection=DFT D3&lang=english > Download the code, compile it and run the calculation with the structures optimized with B3LYP. It > will give you the the dispersion correction within 0.1 second. For most cases, I think a single point > calculation is enough. Hi, I do not agree that in the most cases SP is enough. You could check papers by Grimme and others in which is clearly stated that, DFT without dispersion correction gives totally wrong geometries for certain systems. Personally I've studied several weak adducts bonded with weak hydrogen bonds, in which without addition of dispersion correction on geometry optimization level, you cannot get geometries that are stable enough to reproduce data from experiments. Of course this correction (on geometry optimization level) was not so important in similar adducts bonded with stronger H-bonds. It those cases addition dispersion correction on final geometry was enough to get relatively good energetics and thermodynamics. > Of course, if anybody knows how to run a DFT-D3 calculation on G09 with IOP, I also would like to > know, thanks! In newest revision of Gaussian (D.01) which has just arrived (released on 10 May 2013) there is new keyword implemented for dispersion correction which include two DFT-D3 correction variants. It is called EmpiricalDispersion=PFD, GD3 or GD3BJ and quote from release notes "explicitly request Petersson-Frisch dispersion [Austin12] or Grimme’s D3 dispersion [Grimme10] or D3BJ dispersion [Grimme11].". Best regards, Klemens From owner-chemistry@ccl.net Fri May 17 04:14:00 2013 From: "Mariusz Radon mariusz.radon..gmail.com" To: CCL Subject: CCL:G: b3lyp* Message-Id: <-48711-130517025239-23991-KsttmiQBLdZdkOa1XYrpHw()server.ccl.net> X-Original-From: Mariusz Radon Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=ISO-8859-1 Date: Fri, 17 May 2013 08:52:30 +0200 MIME-Version: 1.0 Sent to CCL by: Mariusz Radon [mariusz.radon++gmail.com] On 16.05.2013 17:44, kalyan onekalyan,yahoo.com wrote: > Hi > > > > http://www.gaussian.com/g_tech/g_ur/k_dft.htm > This is quite good guidline > also you can follow this Linki below > http://www.thch.uni-bonn.de/tc/index.php?section=downloads&subsection=DFT-D3&lang=english > > Download the code, compile it and run the calculation with the > structures optimized with B3LYP. It will give you the the dispersion > correction within 0.1 second. For most cases, I think a single point > calculation is enough. > Of course, if anybody knows how to run a DFT-D3 calculation on G09 with > IOP, I also would like to know, thanks! > Dear Kalyan, I think the original question was about B3LYP* (a modified B3LYP functional with 15% of HF exchange), not about B3LYP-D3 (a method combining B3LYP with a force-field-like correction for dispersion interactions). These two 'variations' of B3LYP are different things and should not be confused with each other. In fact, you may consider a B3LYP*-D3 method as well (a dispersion-corrected functional with 15% of HF exchange). Regards, Mariusz > > ------------------------------------------------------------------------ > *From:* Mariusz Radon mariusz. radon{=}gmail. com > > *To:* "Dhar, Kalyan kumar " > *Sent:* Wednesday, May 15, 2013 9:34 PM > *Subject:* CCL:G: b3lyp* > > > Sent to CCL by: Mariusz Radon [mariusz.radon[a]gmail.com] > On 13.05.2013 11:55, mala alhaji sainna alhajisainna _ yahoo.co.uk > wrote: > > Sent to CCL by: "mala alhaji sainna" [alhajisainna*|*yahoo.co.uk] > > Hi Everyone, > > > > I will highly appreciate it if some one can guide me on how to use > the b3lyp* functional; I tried getting > > an iop for it on the gaussian website but it doesnt seems to be > there and i am not sure how it is used. > > > > Many thanks, > > Mala > > The University of Manchester > > > > Hi, > > You can obtain B3LYP* functional as User-Defined Model based on BLYP > functional. Consult the Gaussian 09 docs about "User-Defined Model": > http://www.gaussian.com/g_tech/g_ur/k_dft.htm > > The values of the coefficients in the model are probably given in the > Marcus Reiher's original paper (DOI: 10.1007/s00214-001-0300-3) > where this functional has been first defined. Anyway, they are the same > as in the original B3LYP, except the factor weighting the HF > exchange (which is 0.15, instead of 0.20). > > Regards, > Mariusz> > > > > > -- > Dr Mariusz Radon, Ph.D. > Coordination Chemistry Group > Faculty of Chemistry > Jagiellonian University > ul. Ingardena 3, 30-060 Krakow, Poland > http://www.chemia.uj.edu.pl/~mradon > the strange characters on the top line to the (_) sign. You can also> > E-mail to subscribers: CHEMISTRY(_)ccl.net > or use:> > E-mail to administrators: CHEMISTRY-REQUEST(_)ccl.net > or use> > > > > > -- Dr Mariusz Radon, Ph.D. Coordination Chemistry Group Faculty of Chemistry Jagiellonian University ul. Ingardena 3, 30-060 Krakow, Poland http://www2.chemia.uj.edu.pl/~mradon From owner-chemistry@ccl.net Fri May 17 04:48:00 2013 From: "Stefan Grimme grimme a thch.uni-bonn.de" To: CCL Subject: CCL:G: D3 in Gaussian (previous message G: b3lyp*) Message-Id: <-48712-130517042741-2138-lyLVK3CYjpJgBU3G27hiQw!^!server.ccl.net> X-Original-From: "Stefan Grimme" Date: Fri, 17 May 2013 04:27:39 -0400 Sent to CCL by: "Stefan Grimme" [grimme,thch.uni-bonn.de] Dear all, because there was a recent post claiming that our D3 method now has found its way into the Gaussian code, please allow me some comments to this (I quote the following from a previous post): >In newest revision of Gaussian (D.01) which has just arrived (released on >10 May 2013) there is new keyword implemented for dispersion correction >which include two DFT-D3 correction variants. It is called >EmpiricalDispersion=PFD, GD3 or GD3BJ and quote from release notes >"explicitly request Petersson-Frisch dispersion [Austin12] or >Grimme’s D3 dispersion [Grimme10] or D3BJ dispersion [Grimme11].". 1. GD3BJ is the recommended, physically more sound version based on the Becke-Johnson damping scheme. GD3 can be used for checking and clarifying the more short-ranged contributions which is smaller than in GD3BJ due to the different damping (the dispersion coefficients are the same). For some functionals like those from the M0X class only GD3 is available because they already include the short/medium-range part in the functional and only require correction for the long-range, London part. 2. This London part of D3 dispersion is NON-EMPIRICAL (not fitted). Its comes out of the TDDFT box. What is fitted is the connection to the short range DFT part and this involves three global parameters similar to most other dispersion corrections (e.g. XDM, vdW-TS, VV10) where this is done similarly. And by the way: if this is called "empirical", then consistently every fitted density functional (e.g. B3LYP) should be called "empirical". The better way to clarify its theoretical basis and to distinguish D3 from other methods is to call it "atom pairwise" correction (or even more precisely: "system-dependent, density-independent, atom pairwise"; in that sense XDM or vdW-TS differs from D3 by being density dependent and VV10 is just "non-local, density dependent"). 3. The "*" in B3LYP* and D3 are not related (although D3 in its B3LYP form can be used for B3LYP* giving a B3LYP*-D3). Hope this helps Stefan