[CP2K-user] [CP2K:21583] Halogen correction and XTB file?

[Andreas Döll]

Dear Mr. Jürg Hutter,

thank You for Your continuous efforts. I will investigate more carefully 
and consider different basissets and potentials; So far for my molecule I 
use TZV2P-MOLOPT with GTH-BLYP and CAMB3LYP as XC functional (see my input 
file below) to determine RESP charges and see if they get more reasonable.

I have to admit, I am very confused about my findings in test/xTB. I tried 
test/QS and test/xTB inputs as you suggested. For cp2k/tests/QS/regtest-dft-vdw-corr-1/dftd2_t1.inp 
and it worked out just fine. I tried tests/xTB/regtest-1/ cho2.inp and it 
doesnt work. Either it says that basis sets are not specified (why?) 
or everytime it says that $info is problematic from the xtb parameter file 
if I put it into the directory...

Two things to note:
- I take xTB0_parameters 
<https://github.com/cp2k/cp2k/blob/master/data/xTB0_parameters> from here 
https://github.com/cp2k/cp2k/tree/master/data 
- I have CP2K version 2024.2, form miniforge distribution as I could not 
get cp2k to install any other way. Could this be the root cause of the 
problems?

I am sure I am missing something very obvious. If you could provide more 
assistance, I would be very grateful.
Thank You in advance!

Sincerely, 
Andreas Doell
Jürg Hutter schrieb am Mittwoch, 25. Juni 2025 um 15:19:39 UTC+2:

> Hi
>
> for RESP charges you have to use DFT. If you don't like the results, 
> investigate if basis sets and/or xc functionals are
> appropriate.
> Other charge methods available are: Mulliken/Lowdin, Hirshfeld, 
> Mulliken-from-IAO, MAO analysis, ...
>
> In xTB (gfn0/1/2) atomic charges are part of the functional definition, no 
> need to extra calculate them.
>
> For correct input files, see the test/QS and test/xTB directories.
>
> regards
> JH
>
> ________________________________________
> From: cp... at googlegroups.com <cp... at googlegroups.com> on behalf of 
> Andreas Döll <andreas... at gmail.com>
> Sent: Tuesday, June 24, 2025 7:05 PM
> To: cp2k
> Subject: Re: [CP2K:21573] Halogen correction and XTB file?
>
> Hello,
>
> Thank You for Your fast response! Even without including RESP section my 
> input file is faulty, so how can I correct it? I want to understand cp2k 
> more, so even if I will not use the xTB in the end, I would like to learn!
>
> Additionally, would other charge methods like Hirsch or mullikan be 
> available when using halogen corrections? On another note, is it possible 
> to include some other corrections to still use RESP charges (which I would 
> strongly prefer) to make the charges on Br more realistic? Any tricks?
>
> Thank you in advance!
>
> Cheers,
> Andreas
>
> Jürg Hutter schrieb am Dienstag, 24. Juni 2025 um 16:14:58 UTC+2:
> Hi
>
> you are calculating RESP charges for a KS-DFT method. Halogen corrections 
> are a thing for tight-binding methods.
> You can't mix the two methods and you can't calculate RESP charges from 
> xTB.
>
> regards
> JH
>
> ________________________________________
> From: cp... at googlegroups.com <cp... at googlegroups.com> on behalf of 
> Andreas Döll <andreas... at gmail.com>
> Sent: Tuesday, June 24, 2025 3:49 PM
> To: cp2k
> Subject: [CP2K:21571] Halogen correction and XTB file?
>
> Dear Cp2k community,
>
> I want to calculate the RESP charges for a benzene ring with 2 Bromium 
> atoms. Attached is my input script resp.inp, which worked so far for small 
> molecules. However, I noticed that the magnitude of the partial charge is 
> quite low for Br (q_i=-0.099), so I read up online and found that you need 
> to include Halogen corrections to properly capture Br in particular, see 
> the related paper Grimme 2017 from the cp2k website. In cp2k this is done 
> via &XTB section and the USE_HALOGEN_CORRECTION keyword, correct?
>
> I tried using the following section:
>
> &XTB
> COULOMB_INTERACTION T
> TB3_INTERACTION F
> CHECK_ATOMIC_CHARGES F
> DO_EWALD T
> USE_HALOGEN_CORRECTION T
> &PARAMETER
> DISPERSION_PARAMETER_FILE dftd3.dat
>
> PARAM_FILE_NAME xTB0_parameters
> &END PARAMETER
> &END XTB
>
> But there are multiple points where I am failing:
>
> The most important point is that I need a xTB_parameters file, but the 
> only file I could find in cp2k repository was the xTB0_parameters file 
> which begins with $info and every time I include it in my script, it says 
> that $info as variable is not defined. However, as far as I understand I 
> need some kind of file for the corrections, or no? If so where can I get 
> the correct file?
>
> Second, am I even using the use_halogen_correction keyword correctly? In 
> the end I want more realistic RESP charges for my molecule, especially on 
> Bromium.
>
> I am very unfamiliar with xtb, so probably this is a very basic question. 
> If you have any other input, I appreciate it as well! I attach my molecule 
> xyz file as well as every other file for testing.
>
> Thank you very much in advance!
>
> Sincerely,
> Andreas Doell
>
>
> --
> 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<mailto:cp2k+uns... at googlegroups.com
> >.
> To view this discussion visit 
> https://groups.google.com/d/msgid/cp2k/51bcff8d-699b-497a-bffb-28460c9fd2d5n%40googlegroups.com
> <
> https://groups.google.com/d/msgid/cp2k/51bcff8d-699b-497a-bffb-28460c9fd2d5n%40googlegroups.com?utm_medium=email&utm_source=footer
> >.
>
> --
> 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<mailto:cp2k+uns... at googlegroups.com
> >.
> To view this discussion visit 
> https://groups.google.com/d/msgid/cp2k/aeaec20c-fe6b-4933-b876-5c55f1058a84n%40googlegroups.com
> <
> https://groups.google.com/d/msgid/cp2k/aeaec20c-fe6b-4933-b876-5c55f1058a84n%40googlegroups.com?utm_medium=email&utm_source=footer
> >.
>

-- 
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 visit https://groups.google.com/d/msgid/cp2k/5a569c21-9006-4fda-ae54-4c1046136ca0n%40googlegroups.com.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20250626/09fb6929/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: linker_opt.xyz
Type: chemical/x-xyz
Size: 1189 bytes
Desc: not available
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20250626/09fb6929/attachment.xyz>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: resp.inp
Type: chemical/x-gamess-input
Size: 3346 bytes
Desc: not available
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20250626/09fb6929/attachment.inp>