Pedro Silva
pedros@ufp.edu.pt
UV/Vis absorption occurs from the ground state, and therefore you must use ground-state-optimized geometries for your TDDFT in this instance.
Fluorescence, in contrast, occurs from the relaxed geometry of an excited state. Therefore, if you are interested in computing fluorescence wavelengths you must optimized the excited state you are interested on before attempting TDDFT .
Pedro