Hi everybody,

I am from the EPR community and working on the encapsulation of endohedral fullerene (N@C60) into different host molecules. To get a better understanding of the complex's electronic structure, I try DFT on those guest-host complexes.

The parameter what I am looking for is the g-value and the hyperfine coupling constant of the atomic nitrogen of the endohedral fullerene.

The problem is, that I don't find the right parameter, like functionals and basis sets for the complexes as well as if I shoud use an extra EPR basis set.

Up to now, I tried the B86 functional with the basis sets: SV, def2/J with different EPR basis sets (EPR-II, EPR-III, IGLO-II, IGLO-III and aug-cc-pVTZ-J) with a restricted (RHF) and unrestricted (UHF) settings. Next to the MOs, I am printing the g-value and the hyperfine coupling. Here, all isotropic g-values are fitting the literature value, but the computed hyperfine constants are not. Some of are to very high (9 times to high) some of them are negative.

Maybe someone can help me, choosing the right parameters for my problems, that would be amazing.

Best,

Marco