[adelaro]

Hello,

Does anyone have experience with doing excited-state geometry optimizations with TD-DFT? I am studying a fluorescent molecule and have performed a TD-DFT computation to optimize the geometry of the first (singlet) excited state, and I am not sure if the output is what I want. Specifically, what should the orbital population analysis show you in this case? In my output file, the Occupied and Vacant orbitals listed are the same as those in the ground state (slightly different energies, but the pattern of occupancy is the same). Alternatively, viewing the MOs in AGUI, it shows all electrons paired, i.e. the two highest-energy electrons paired in the same orbital, where I would expect them to appear to occupy two different orbitals, if this is the first excited state. Does the output show you the ground-state electron configuration, just in the excited state optimized geometry? Or does this indicate that something went wrong with my calculation?

Thanks!