[CP2K-user] [CP2K:16309] van der Waals cutoff vs. system size

[Binquan Luan]

Hi Juerg,
Thanks for clarification.  Can you help explain how the van der Waals 
interaction is calculated when the cutoff distance is much larger than the 
primitive cell. One example is a small molecule on the material surface. To 
calculate the interaction between a small molecule and the substrate 
surface, is the substrate surface duplicated (with the PBC)? 
Best,
Binquan

On Thursday, November 25, 2021 at 3:19:40 AM UTC-5 jgh wrote:

> Hi
>
> Minimum image convention is not applied in PBC calculations in CP2K.
>
> regards
>
> Juerg Hutter 
> --------------------------------------------------------------
> Juerg Hutter Phone : ++41 44 635 4491 <+41%2044%20635%2044%2091>
> Institut für Chemie E-mail: hut... at chem.uzh.ch 
> Universität Zürich 
> Winterthurerstrasse 190
> CH-8057 Zürich, Switzerland
> ---------------------------------------------------------------
>
> -----cp... at googlegroups.com wrote: -----
> To: "cp2k" <cp... at googlegroups.com>
> From: "Binquan Luan" 
> Sent by: cp... at googlegroups.com
> Date: 11/24/2021 07:43PM
> Subject: [CP2K:16303] van der Waals cutoff vs. system size
>
> Dear all,
> For DFT calculations with van der Waals corrections, I am wondering what 
> the right cutoff distance should be. In the manual, I found
>
> R_CUTOFF {Real} 
> Range of potential. The cutoff will be 2 times this value [Edit on GitHub] 
> This keyword cannot be repeated and it expects precisely one real. 
> Default value: 1.05835442E+001 
> Default unit: [angstrom]
>
> If the default range of potential is 21 angstrom, with the minimum image 
> convention used for PBC, the system size (in each dimension) should be at 
> least 42 angstrom that is much larger than most systems reported in 
> literature. Do I miss anything here? 
>
> Thanks a lot for help!
>
> Binquan
>
> -- 
> You received this message because you are subscribed to the Google Groups 
> "cp2k" group.
> To unsubscribe from this group and stop receiving emails from it, send an 
> email to cp2k+uns... at googlegroups.com.
> To view this discussion on the web visit 
> https://groups.google.com/d/msgid/cp2k/1783347c-3b8d-4f7b-9cb9-9d70ec6698e1n%40googlegroups.com
> .
>
>

-- 
You received this message because you are subscribed to the Google Groups "cp2k" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cp2k+unsubscribe at googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/cp2k/84cebd98-c3a5-4335-986d-ad2e0ab27528n%40googlegroups.com.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20211125/2b43f5e0/attachment.htm>