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Pavlo Solntsev
pavlo.solntsev@gmail.com

P.S. Definitely, this discussion should be added to the manual.

-Pavlo.





On Wed Nov 12 '14 10:41am, Alex Granovsky wrote
-----------------------------------------------
>Pavlo,

>this error means that the reference (i.e. HF or DFT) state violates
>the aufbau principle. In this context, aufbau principle states that
>the energy of HOMO should be less than the energy of LUMO. TDDFT and
>TDHF computations are only meaningful when aufbau principle is held.

>As a workaround, try to find an alternative SCF solution. E.g. you
>can swap HOMO and LUMO and try to converge SCF again. Nonetheless,
>even with alternative SCF solution one typically can expect small
>HOMO-LUMO gap and very low TDDFT excitation energy. It could be
>helpful to perform MCSCF to check wf. for multireference character

>All the best,
>Alex
>
>
>On Tue Nov 11 '14 7:51pm, Pavlo Solntsev wrote
>----------------------------------------------
>>Alex,

>>By doing a TDDFT for a system i found this error. SCF minimization was finished successfully, but the error occurs at TDDFT stage. Could you please advise me how to solve this problem? I saw, AUFBAU principle was mentioned in CI section of the manual, but no word was said about this principle for TDDFT case. My input file:

>> $CONTRL SCFTYP=RHF MAXIT=200 ICHARG=1 MULT=1 NZVAR=1
>> inttyp=hondo icut=11 itol=30 dfttyp=pbe96 cityp=tddft $END
>> $BASIS GBASIS=n31 ngauss=6 ndfunc=1 npfunc=1  $END
>> $tddft nstate=5 istsym=1 mult=1 $end
>> $dft nrad=99 lmax=41 $end
>> $SCF DIRSCF=.TRUE. $END
>> $DATA
>>Cn 2

>>.....
>> $end

>>I use Firefly version 8.1.0, build number 9035 .

>>Thank you.

>>-Pavlo.