Firefly and PC GAMESS-related discussion club

Learn how to ask questions correctly  
We are NATO-free zone

Doubts regarding TDDFT calculations and excited state determination....

Siddheshwar Chopra

Dear Firefly Users,

I am stuck up with the concept of excited states. Specifically speaking with some doubts in TDDFT.

What is meant by NSTATE in FIREFLY i/p file? I know ISTATE is singlet or doublet... NSTATE seems to be the no. of excited states I wish to study.. When I read the firefly TDDFT o/p file.. I see that for every EXCITED STATE, I have a set of probable transitions... THIS IS WHAT IS CONFUSING ME ...

What I assumed till now is that first excited state is LUMO. But now in the firefly o/p file I see HOMO--> LUMO transitions occuring for almost all excited states 1,2,3 etc.. So my concept of Excited state is unclear... I just open the TDDFT o/p fie with Gausssum and get the spectra. I also get the probabilities of the particular transitions alongwith their osc. strengths. Probabilities must be calculated by squaring and adding the SAPs. But I can't visualize the excited state here. Please explain to me this.

Kind Regards,

[ Previous ] [ Next ] [ Index ]           Thu Sep 11 '14 7:21am
[ Reply ] [ Edit ] [ Delete ]           This message read 420 times