2 Thomas: > Or you can also use the simple dipole correction which was actually > developed for charged (particles on) surfaces, see, e.g.,
No, I think I wish the opposite: currently my pseudo-anion is neutral, but the *real* one should not be -- and, hence, image charge interaction is missing... I'd like to get it back. Of course, I it is possible and straightforward to keep an extra electron on chlorine and simulate the system with real -1 charge, that all what you've said are relevant and good. So, Giuseppe > I've used a semiempirical U value of 4 eV on the Cl 3p electrons to > keep together the electrons of Cl- in photosystem II. Could you elaborate more on that? Or may be you've published the results -- I could read and reference them. Thanks to all of you, colleagues! -- I. On Tue, Sep 13, 2016 at 11:34 AM, Thomas Brumme <[email protected]> wrote: > Or you can also use the simple dipole correction which was actually > developed for charged (particles on) surfaces, see, e.g., > > Phys. Rev. B 59, 12301 (1999) > > Phys. Rev. B 63, 205426 (2001) > > > On 09/13/2016 05:22 PM, Giuseppe Mattioli wrote: >> P.S. >> If your main concern is the vertical interaction between charges you >> can discard the interaction by using the ESM boundary conditions in a >> vacuum-slab-vacuum geometry (see the manual, the implementation is >> very simple and the calculation is stable in my hands). >> HTH >> Giuseppe >> >> Quoting Ilya Ryabinkin <[email protected]>: >> >>> Hi Thomas: >>> SIC is definitely one of the ways to address this problem, but we also >>> thinking about tconstrained DFT approach. Unfortunately, this is more >>> i) long-term investment, ii) this doesn't rule out the problem of >>> image charge completely if a slab is too thin. >>> >>> BTW: it is written in a manual >>> >>>> This approach has known problems for dissociation mechanism driven >>>> by excess electrons. >>> >>> I wonder, what are these problems? >>> >>> >>> -- >>> I. >>> >>> On Tue, Sep 13, 2016 at 10:01 AM, Thomas Brumme >>> <[email protected]> wrote: >>>> Hi Ilya, >>>> >>>> I wonder if the SIC implementation in CP can help: >>>> >>>> http://www.quantum-espresso.org/wp-content/uploads/Doc/cp_user_guide/node11.html >>>> >>>> Unfortunately, I'm not familiar with CP... >>>> >>>> Regards >>>> >>>> Thomas >>>> >>>> >>>> On 09/13/2016 03:44 PM, Ilya Ryabinkin wrote: >>>>> 2NIcola: >>>>> >>>>>> If I understand this correctly, it seems a less satisfactory answer that >>>>> just having the uniform jellium background? >>>>> >>>>> No. In particular, I have Cl- species in my system, but there is no >>>>> way in common GGAs to keep an electron on chlorine -- due to self >>>>> interaction the electron is too weakly bound (if any) to Cl and DFT >>>>> gives a completely wrong, de-localized solution for an extra electron. >>>>> Neutralizing background will simply eat up the field of this >>>>> delocalized electron and I'll be simulating a system which resembles >>>>> more a *neutral* Cl atom on a slab rather than an anion. >>>>> One of the possible ways to work around -- is to devise a >>>>> pseudopotential for Cl with the configuration [He] 2s^2 2p^5 3s^2 >>>>> 3p^6, which has a hole in 2p and an extra electron in 3p, then "bury" >>>>> the hole inside a pseudopotential... This solution, however, leads to >>>>> the apparent lack of charge-image interaction since the resulting >>>>> pseudoatom is neutral (in fact, it looks like Ar). >>>>> >>>>>> the state of charge of your particle >>>>>> will be determined by the physics - i.e. the xc functional will decide >>>>>> how much charge should sit on the particle >>>>> I wish it could be true... but not for the common DFA-s >>>>> >>>>>> Which capability? Adding an empirical extra term in the forces for >>>>>> the charge? >>>>> Yes. I'm wondering if some one already did this. I can do it myself, >>>>> but for the sake of not re-inventing the wheel... >>>>> >>>>> I. >>>>> >>>>> On Tue, Sep 13, 2016 at 6:26 AM, Lorenzo Paulatto >>>>> <[email protected]> wrote: >>>>>> Hello, >>>>>> it is not too clear to me what you need, but is something like >>>>>> this: http:// >>>>>> journals.aps.org/prb/abstract/10.1103/PhysRevB.89.245406 ? >>>>>> >>>>>> It is implemented in the upcoming version 6.0 of QE, >>>>>> The feature is still disabled in the downloadable beta versione, but it >>>>>> is >>>>>> enabled in the last daily snapshots at http://qe-forge.org/snapshots/ (no >>>>>> guarantee anything works). >>>>>> >>>>>> hth >>>>>> >>>>>> On Monday, 12 September 2016 18:13:25 CEST Ilya Ryabinkin wrote: >>>>>>> Dear colleagues: >>>>>>> I am simulating dynamics of a charged particle on a metallic slab. To >>>>>>> avoid difficulties with Coulomb energy of a charged cell, we use a >>>>>>> core-hole trick to introduce a compensatory positive charge directly >>>>>>> into a particle. However, the image-charge interaction is clearly >>>>>>> absent and we would like to bring it back. >>>>>>> >>>>>>> Did anyone bother him/herslef to implement is in QE? I know VASP has >>>>>>> this capability, but it is out of scope. >>>>>>> >>>>>>> Thanks in advance, >>>>>>> I. >>>>>> -- >>>>>> Dr. Lorenzo Paulatto >>>>>> IdR @ IMPMC -- CNRS & Université Paris 6 >>>>>> +33 (0)1 44 275 084 / skype: paulatz >>>>>> http://www.impmc.upmc.fr/~paulatto/ >>>>>> 23-24/4é16 Boîte courrier 115, >>>>>> 4 place Jussieu 75252 Paris Cédex 05 >>>>>> >>>>>> _______________________________________________ >>>>>> Pw_forum mailing list >>>>>> [email protected] >>>>>> http://pwscf.org/mailman/listinfo/pw_forum >>>>> >>>> -- >>>> Dr. rer. nat. Thomas Brumme >>>> Max Planck Institute for the Structure and Dynamics of Matter >>>> Luruper Chaussee 149 >>>> 22761 Hamburg >>>> >>>> Tel: +49 (0)40 8998 6557 >>>> >>>> email: [email protected] >>>> >>>> _______________________________________________ >>>> Pw_forum mailing list >>>> [email protected] >>>> http://pwscf.org/mailman/listinfo/pw_forum >>> >>> >>> -- >>> ******************************************************* >>> Ilya Ryabinkin >>> Postdoctoral Scholar >>> Physical and Environmental Sciences >>> University of Toronto Scarborough >>> http://www.utsc.utoronto.ca/~aizmaylov/Members.html >>> ******************************************************* >>> >>> _______________________________________________ >>> Pw_forum mailing list >>> [email protected] >>> http://pwscf.org/mailman/listinfo/pw_forum >> > > -- > Dr. rer. nat. Thomas Brumme > Max Planck Institute for the Structure and Dynamics of Matter > Luruper Chaussee 149 > 22761 Hamburg > > Tel: +49 (0)40 8998 6557 > > email: [email protected] > > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum -- ******************************************************* Ilya Ryabinkin Postdoctoral Scholar Physical and Environmental Sciences University of Toronto Scarborough http://www.utsc.utoronto.ca/~aizmaylov/Members.html ******************************************************* _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
