use the empirical correction term of DFT-D3 in the classical MD

[Marco]

Dear JianBiao,

Yeah that sounds like a reasonable approach. You are using QM data derived 
from DFT-D3 calculations to parameterize a force field of a certain 
functional form (presumably employing the Tang-Toennies damping function as 
the non-bonded component in addition to bond/angle/dihedral etc. terms). 
Your QM data from the DFT-D3 calculations account for dispersion effects 
and this should transfer over into your force field parameterization in the 
case of a good fit. As you know since you work with parameterization, one 
measure of a good fit is whether your parameterized force field 
calculations reproduce your QM reference data set and certain properties of 
your system. Anthony J. Stone has published a lot of good work in this 
field. 
(http://www-stone.ch.cam.ac.uk/personal/bibliography.html)

What do you mean by add the DFT-D3 to the classical MD parts?

Best regards,
Marco

On Friday, May 23, 2014 9:38:32 PM UTC-4, JianBiao wrote:
>
> Dear Marco,
>     Thank you for your reply. I am sorry I didn't say my question clearly. 
> During the force-matching process, one can use the forces calculated from 
> the PBE-AIMD as the references, then one can parameterize some parameters 
> in the force field such as V(A, B, .. C6=0, C8=0). Because PBE fails to 
> describe the dispersion effects, one cannot get the C6 and C8 from the 
> force-matching. Then during the MD simulation, one can use the Grimme's 
> damped empirical correction terms to calculate the dispersion parts. So I 
> think this method is reasonable. Could you please give some comments? Could 
> someone please help to add the DFT-D3 to the classical MD parts?
>
> Best, JianBiao
>    
>
>
>
>
> 在 2014年5月24日星期六UTC+8上午7时45分00秒，Marco写道：
>>
>> Hello,
>>
>> DFT and classical MD are two very different model chemistry's. The 
>> parameterizations for BMHFTD (if and when available) and DFT-D3 are 
>> completely different. It would be unsound to transfer Grimme's damped 
>> empirical correction terms into a classical MD force field in such a 
>> straightforward manner. At least I have not seen it done in the literature. 
>>
>> Regards,
>> Marco
>>
>> On Friday, May 23, 2014 8:23:10 AM UTC-4, JianBiao wrote:
>>>
>>> Dear CP2K developers,
>>>     Is it possible to use DFT-D3 to calculate the dispersion energies 
>>> during the classical MD simulations? Because the dispersion term in  
>>> CP2K_INPUT <http://manual.cp2k.org/trunk/CP2K_INPUT.html> / FORCE_EVAL<http://manual.cp2k.org/trunk/CP2K_INPUT/FORCE_EVAL.html>
>>>  / MM <http://manual.cp2k.org/trunk/CP2K_INPUT/FORCE_EVAL/MM.html> / 
>>> FORCEFIELD<http://manual.cp2k.org/trunk/CP2K_INPUT/FORCE_EVAL/MM/FORCEFIELD.html>
>>>  / NONBONDED<http://manual.cp2k.org/trunk/CP2K_INPUT/FORCE_EVAL/MM/FORCEFIELD/NONBONDED.html>
>>> /
>>> BMHFTD<http://manual.cp2k.org/trunk/index.html#CP2K_INPUT/FORCE_EVAL/MM/FORCEFIELD/NONBONDED/BMHFTD.html>
>>>  is similar to Grimme's damped empirical correction, one can use the 
>>> dft-d3 to calculate the dispersion energy and corresponding forces. Could 
>>> you please give some suggestions? 
>>>
>>> Best wishes
>>> JianBiao
>>>
>>
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