Is there any free GAMESS input file maker for Mac OS?
If you can give me the requisite keywords for TD-DFT in GAMESS, it's not hard to add that to Avogadro

I've never done TDDFT in GAMESS because I use other programs, but given a link to the docs, it's easy enough to enable more drop-down menus.

That said, you can interactively edit the text in the Avogadro input for any quantum program (not just GAMESS).



If you don't want to use Avogadro, the "native" program for GAMESS is MacMolPlt which was developed in the Gordon group itself. I haven't checked, but I'd assume it supports TDDFT options, since it enables pretty much everything else in GAMESS.