[CP2K-user] [CP2K:17031] TDDFPT using PBE0 in version 9.1 versus in 4.1

[Jürg Hutter]

Hi

this input should work with the current Trunk version of CP2K. You can find many
examples in tests/QS/regtests-tddfpt-*
Please note that we recently fixed a bug in the HFX-tddft code.

best, Juerg

&FORCE_EVAL
  METHOD Quickstep
  &PROPERTIES
    &TDDFPT
       KERNEL FULL
       NSTATES      5
       MAX_ITER    50
       CONVERGENCE [eV] 1.0e-7
    &END TDDFPT
  &END PROPERTIES
  &DFT
    &QS
      METHOD GPW
    &END QS
    &AUXILIARY_DENSITY_MATRIX_METHOD
      METHOD basis_projection
      ADMM_PURIFICATION_METHOD none
    &END
    &XC
      &XC_FUNCTIONAL PBE0
      &END
    &END XC
    ........

________________________________________
From: cp2k at googlegroups.com <cp2k at googlegroups.com> on behalf of Maria Fumanal <mfumanal at gmail.com>
Sent: Tuesday, May 24, 2022 5:22 PM
To: cp2k
Subject: [CP2K:17029] TDDFPT using PBE0 in version 9.1 versus in 4.1

Dear CP2K community,

I wanted to reproduce the TDDFPT results of a small system obtained with PBE0 with CP2K 4.1 and 9.1,
but I have seen that the TDDFPT input section has changed a lot and I do not manage to make it work to obtain the same results.

with CP2K 4.1 the simplest TDDFPT input I used to use is (see pbe0_41.inp/out):

  &TDDFPT
     NSTATES     3
     MAX_ITER    2000
     CONVERGENCE [eV] 1.0e-4
     &MGRID
        CUTOFF 200
     &END
  &END TDDFPT

This above does not work with the 9.1 version anymore.
The only way I have manage to make it work without failing is specifying the &XC subsection this way:

  &TDDFPT
     &XC
       &XC_FUNCTIONAL
          &PBE
            SCALE_X 0.75
            SCALE_C 1.0
          &END PBE
       &END XC_FUNCTIONAL
     &END XC
     NSTATES     3
     MAX_ITER    2000
     CONVERGENCE [eV] 1.0e-4
     &MGRID
        CUTOFF 200  # separate cutoff for TDDFPT calc
     &END
  &END TDDFPT

It works but the TDDFPT results I obtained are very far from the ones I get with the older version. (see pbe0_91_XC.inp/out)

If I do not specify this &XC section it fails (see pbe0_91.inp/out, error "derivatives bigger than 1 do not work correctly ")

If I specify the same &XC settings than for the Ground State including the &HF section, &vdW_POTENTIAL, etc it fails (see pbe0_91_XC_HF.inp/out, error "ADMM is not implemented for a TDDFT kernel XC-functional which is different from the one used for the ground-state calculation. A ground-state 'admm_env' cannot be reused.)

Does anyone know why this is happening and how to solve it?

Thanks a lot in advance,

Maria

--
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<mailto:cp2k+unsubscribe at googlegroups.com>.
To view this discussion on the web visit https://groups.google.com/d/msgid/cp2k/a07282d7-2ccf-4847-9213-2ff78a3a09bdn%40googlegroups.com<https://groups.google.com/d/msgid/cp2k/a07282d7-2ccf-4847-9213-2ff78a3a09bdn%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/ZR0P278MB0759381AD11C9ECD9A586A349FD69%40ZR0P278MB0759.CHEP278.PROD.OUTLOOK.COM.