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sanya
sanya@photonics.ru

the problem is (1) the method of TDDFT and (2) the basis set. You will also get similar results with CIS, so it is not the problem of a particlar functional but probably of a single-excitation method as such. I've performed several calculations of benzene with different functionals, basis sets and methods. In a day or two I'll prepare a digest of my experiments. In short, only XMCQDPT gives tractable results, and these results also depend on the basis set (the larger basis, the worse!). On the other hand, CIS, TD-PBE0 or TD-B3LYP with relatively small basis set (such as 6-31G(d,p)) are OK. But this may not be the case with your real molecule.

[ This message was edited on Tue Dec 30 '08 at 4:56am by the author ]