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Jonas Baltrusaitis
jonas-baltrusaitis@uiowa.edu

**** ERROR, RUNTYP=OPTIMIZE REQUIRES ENERGY GRADIENT.
THIS IS IMPOSSIBLE WHILE STATE AVERAGING. NAVG=    5

Should I just ask for a brightest state gradient? Also, activate tracking of all states? It's 4 excited states I am working with, so would this work?

$MCSCF ISTATE=5 ntrack=5

Would this optimize to 4th excited state and track all 5 states (ground+4 excited)? Is there any value of state tracking in state averaged calculations?

Jonas

On Sat Jul 31 '10 1:56am, Jim Kress wrote
-----------------------------------------
>NBOs and NOs are not the same.  In addition, the NBO analysis will specifically decomopose the NBO orbitals according to nuclear center, bonding type, and AO contribution.

>Look here for more info:

>http://www.chem.wisc.edu/~nbo5/http://www.chem.wisc.edu/~nbo5/http://www.chem.wisc.edu/~nbo5/http://www.chem.wisc.edu/~nbo5/

>Jim

>On Thu Jul 29 '10 4:49am, Jonas Baltrusaitis wrote
>--------------------------------------------------
>>I got similar suggestion from Sanya only he suggested natural orbitals of interest.

>>Maybe I am not interpreting right: all I need is emission spectrum. So I do not have particular bonds or orbitals in mind, I only need to optimize to certain excited state or averaged states to get decent representation of fluorescence spectra. Does that change anything or I still have to select bond or orbital wise?

>>Also, would that make these calculations state specific or state average?

>>Jonas
>>
>>
>>On Wed Jul 28 '10 6:35pm, Jim Kress wrote
>>-----------------------------------------
>>>Try doing a NBO analysis.  Then select your active space from the set of NBOs (or even NLMOs) that correspond to the atoms and/or bonds of primary concern to you.

>>>This is how I usually set-up my MCSCF/ CASSCF calculations.

>>>Jim

>>>On Wed Jul 28 '10 3:15am, sanya wrote
>>>-------------------------------------
>>>>On Tue Jul 27 '10 4:16pm, Jonas Baltrusaitis wrote
>>>>--------------------------------------------------
>>>>>From what I've read in the literature CASSCF should be a good thing for my molecules since it can deal with multireference character and bond breaking. I am a bit hesitant since I am not sure how to select the active space. Would TDDFT do in selecting which orbitals and electrons to correlate? Is there a rule of thumb?

>>>>DFT (as well as HF) orbitals are not very good as starting MOs. Natural orbitals are better. Unfortunately, there is no rule of thumb in selecting the active space, just a common sense and a chemical insight :) In fact, it is individual for each molecular system.

[ This message was edited on Sun Aug 1 '10 at 5:50pm by the author ]