[CP2K-user] [CP2K:19101] No agreement between the LR and RT absorption spectra

[Victor Volkov]

Dear Natalia:
If I understand right, under the

&GLOBAL
  PROJECT Ag6
  RUN_TYPE RT_PROPAGATION
  PRINT_LEVEL LOW
&END GLOBAL

you do not compute properties of UV optical transitions
but a dielectric response in the ground state.

Victor


On Mon, Jul 10, 2023 at 11:55 AM Natalia K <natalja.lipina at gmail.com> wrote:

> Dear community,
>
> I am calculating the absorption spectra for a silver chain using both
> linear response (TDDFPT) and real-time propagation implemented in CP2K 9.1.
> Within the RT propagation, I apply a delta kick in all three directions and
> then take the Fourier transform of the dipole moment and get the average
> (over three directions) spectrum that is in a very good agreement with the
> literature. In particular, with another GGA linear-response calculation
> with the Gaussian code (image attached, top - my results, bottom -
> reference). Within the TDDFPT approach, I calculate the oscillator strength
> which should give the same frequencies as the real-time approach, but it
> doesn't. In the figure attached, the oscillator strength is plotted with
> impulses. I tested many different parameters but LR never agrees with RT. I
> also tested a simpler system, a water molecule, and got a better agreement
> between the two methods, but still not as perfect as here, for instance:
> https://nwchemgit.github.io/RT-TDDFT.html#absorption-spectrum-of-water
>
> I would appreciate any help or suggestion. I attach both RT and LR input
> files used to obtain the results on the figure.
>
> Best regards,
>
> Natalia
>
> --
> 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/c1c50acf-05be-49c1-80d3-da0dc60210c1n%40googlegroups.com
> <https://groups.google.com/d/msgid/cp2k/c1c50acf-05be-49c1-80d3-da0dc60210c1n%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 on the web visit https://groups.google.com/d/msgid/cp2k/CAK%2B-SSikeZrD0otZ1O%2BFU%3D3x6LNrNOTWWH-iNLt1EqcE7C%3DBgA%40mail.gmail.com.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20230710/3a9abffc/attachment.htm>