Firefly and PC GAMESS-related discussion club

 
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Pavlo Solntsev
pavlo.solntsev@gmail.com

Only careful analysis of the literature may give you answer to the question. Some things you should think about:

Are you sure TDDFT is good?
basis set?
functional? (Are you sure B3LYP1 is good? Examples......)
Rydberg states? (Very common problem for small molecules. )

All questions you have addressed are related to a general methodology and unfortunately, the best friend(s) here is a literature and examples/benchmarks.

Good luck.
Pavel.



On Sun Mar 30 '14 3:36pm, Alisher wrote
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>Dear Alex and Firefly users,
>I computed UV/Vis spectra of C=O containing aromatic compounds by TDDFT (B3LYP1). But, I can’t found agreement between experiment and TDDFT. In the experiment, usually, n-pi* transition of the C=O group observed in the longest wavelength region then pi-pi* transition. Besides, n-pi and pi-pi* transitions also observed pi-pi* transition caused by charge transfer from aromatic fragment to the C=O group.
>Who can help me to choice the best DFT method for modeling UV/Vis?
>Thanks in advance!
>