[CP2K:2930] Re: DFT-D

[hut... at pci.uzh.ch]

Hi

we do have analytic gradients for the C9 terms. Grimme was
negative in part because of the costs of their numerical
gradients. For small systems the C9 terms are certainly not important.
We do have the possibility to do C9 using fixed C6. This speeds
up the calculation also.
The following example shows the improvements of D3 for surface
systems, although I don't know if this includes the C9
http://www.scm.com/News/DFT-D3.html
With VERBOSE_OUTPUT you can check easily how big the contribution
of E9 is.

regards

Juerg


--------------------------------------------------------------
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
---------------------------------------------------------------

-----cp... at googlegroups.com wrote: -----

To: cp2k <cp... at googlegroups.com>
From: Matt W <mattwa... at gmail.com>
Sent by: cp... at googlegroups.com
Date: 11/22/2010 02:42PM
Subject: [CP2K:2930] Re: DFT-D

Hi,

> This is an example for the new D3 method
>          DISPERSION_FUNCTIONAL PAIR_POTENTIAL
>          &PAIR_POTENTIAL
>             TYPE DFTD3
>             REFERENCE_FUNCTIONAL BLYP
>             CALCULATE_C9_TERM .TRUE.
>             PARAMETER_FILE_NAME dftd3.dat
>             R_CUTOFF 15.0
>          &END PAIR_POTENTIAL
>       &END vdW_POTENTIAL
>

sorry, off topic, but as this is here...

Do you recommend the three body (C9) term?  It seems Grimme was
somewhat dubious about it in the original JCP 2010 paper?

Cheers,

Matt

-- 
You received this message because you are subscribed to the Google Groups "cp2k" group.
To post to this group, send email to cp... at googlegroups.com.
To unsubscribe from this group, send email to cp2k+uns... at googlegroups.com.
For more options, visit this group at http://groups.google.com/group/cp2k?hl=en.