Basis set or method for Fe complex

[methane]

I want to calculate [Fe(C2O4)3]3- excited state in solution.

First I calculated the spectrum using TD-B3lyp and SVP basis set. The spectrum I got is quite different from the experimental results. In specific , much lower, about 1eV,  than the exp results.

How can I do to improve?

[antti_karttunen]

Have you already tried using a triple-zeta basis set? If B3LYP/SVP fails, you could see if B3LYP/TZVP yields better results. I think BP86/SVP and BP86/TZVP would be other combinations worth testing.