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Re^2: wrong oscillator strengths for high symmetry molecules in TDDFT calculation

Andrii Kulinich

>1. I did not see anything wrong with the example you attached.
The first seven transitions in the TDDFT spectrum of ferrocene have zero oscillator strengths, and this should be wrong (on my opinion).

>2. As to second part of your question, could you please be a bit
>more specific. It is hard to answer without looking into actual
>output files. Note, in C2 group, there are no forbidden transitions
>at all. Does your question mean that you got large transition
>moments for forbidden transitions in Ci group?
I did not get large transition moments for forbidden transitions in Ci group. Nevertheless, I believed that for a molecule with C2 symmetry the B-symmetry transitions should be "more allowed" than A-symmetry transitions, but in some cases of C2-symmetry bis-dyes it was vise versa.
The other point is that (according to the classical molecular exciton theory) in bis-dyes with Ci symmetry of their molecules (angle of 180 degrees between their chromophores) the long-wavelength allowed transition should be more intensive then the short-wavelength one(1-st and 3-rd transitions correspondingly in the attached file), but TDDFT calculation gives opposite result.


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[ bind3_ci_td.7z ] Bis-dye TDDFT task

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