[CP2K:1629] Re: GRIMME and parameters

[Juerg Hutter]

http://cp2k.berlios.de/manual/CP2K_INPUT/FORCE_EVAL/DFT/XC/VDW_POTENTIAL/PAIR_POTENTIAL.html



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Juerg Hutter                   Phone : ++41 44 635 4491
Physical Chemistry Institute   FAX   : ++41 44 635 6838
University of Zurich           E-mail: hut... at pci.uzh.ch
Winterthurerstrasse 190
CH-8057 Zurich, Switzerland
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On Mon, 8 Dec 2008, Daniele Passerone wrote:

>
> Thank you Juerg. Is there some special way to change the parameters in
> the Grimme case?
> Thanks again,
> Daniele
>
>
> On Dec 8, 2:42 pm, Juerg Hutter <hut... at pci.uzh.ch> wrote:
>> Hi Daniele
>>
>>> Dear developers
>>
>>> The DFT-D functional[GRIMME 2006] is implemented in the code. The
>>> example in the regtests refers to the PBE functional. The paper by
>>> Grimme explains that in principle one could (upon reparametrization of
>>> the functional) use the pairwise correction terms in connection with
>>> any functional, and for any element of the periodic table. Eventually,
>>> the paper seems to refer mostly on PBE and on atoms up to Xe.
>>
>>> So I have two questions:
>>
>>> 1) can I use GRIMME with other functionals in cp2k?
>>
>> Yes, the default scaling parameters for some functionals from the
>> Grimme Paper are applied. You can always use your own parameter by
>> specifying the value in the input. Check the output if the value
>> used is what you expected.
>>
>>
>>
>>> 2) What does it happen if I include elements that are not present in
>>> the paper [for example, a hydrocarbon on Gold]?
>>
>> The code should stop if there are no default values and you are not
>> defining any values in the input. I just checked and it seems that
>> instead of stopping the code proceeds with wrong parameters.
>> We will fix this as soon as possible.
>> For your problem I suggest that you pick some reasonable values for
>> Au and set them through the input. Of course in the next step
>> you should check that those values work as expected.
>>
>> regards
>>
>> Juerg
>>
>>> Thank you in advance,
>>
>>> Daniele Passerone
> >
>