frequency mismatch in cc density module

[xiang]

Hi there,
I'm calculating an ADC(2) level excitation energies. So after the preoptimization converged and called cc density module to calculate overlap between left/right vectors (guess in cc_1den), there is an error by printing two unequal frequencies and following:

=================
internal module stack:
--------------------------
    ricc2
    cc_exci
    cc_1den
    ccintleftvec
=================
frequency mismatch
ricc2 ended abnormally

Would someone lend a hand?
Best,
Xiang

[Arnim]

Hello,

could you share what was printed before that?

Cheers,
Arnim

[xiang]

thanks for replying, sure, please check the following:
     +=======================================================================+
     | type: RE0                    symmetry: a               state:    3    |
     +-----------------------+-----------------------+-----------------------+
     | occ. orb.  index spin | vir. orb.  index spin |  coeff/|amp|     %    |
     +=======================+=======================+=======================+
     |   43 a       43       |   46 a       46       |   0.70140      49.2   |
     |   43 a       43       |   47 a       47       |  -0.66027      43.6   |
     |   45 a       45       |   46 a       46       |   0.14644       2.1   |
     |   43 a       43       |   58 a       58       |  -0.08214       0.7   |
     +=======================+=======================+=======================+
     norm of printed elements:  0.95611



     Info: copy ADC(2) right eigenvectors into left eigenvector files.


                    ========   CC DENSITY MODULE   ========

                      current wave-function model: ADC(2)

  calculating overlap between    3 left and right vector(s)
    density nr.      cpu/min        wall/min    L     R
   ------------------------------------------------------
         1             0.20            0.01    LE0    RE0
-6.240487094410323E-002 -6.240332690596439E-002

========================
internal module stack:
------------------------
    ricc2
    cc_exci
    cc_1den
    ccintleftvec
========================

frequency mismatch
ricc2 ended abnormally

[Arnim]

I am not sure what went wrong there. You could try to simply restart the job.
If that doesn't help, change the number of excitation (nexc or npre). That can sometimes lead to a better numerical behavior.

Best
Arnim

[xiang]

Dear Arnim,
many thanks, I will try with a new input.
Best,
Xiang

[lauredethieulloy]

Hi,

while running on Turbomole 7.5, I encountered the same error. Running it again or changing the number of excited state lead to the same error.

how did you overcome this problem ?

Best,

Laure

[christof.haettig]

It should not happen with newer versions.

If it happens (with older versions) you can fix it by
  - run an initial calculation with higher convergence threshold in $excitations
  - if it stops with this error, restart with a reduced convergence threshold.
It typically happens if you have (near) degeneracies between states within the same computational irrep. Thus, if your structure has any point group symmetry, use it in the calculation.