Absolute configuration of C76 from optical rotatory dispersion.

The absolute configuration of C76 has been determined as (+)589-(fC)-C76 , for the first time, by comparing the experimental and predicted optical rotatory dispersion (ORD) patterns. The experimental ORD pattern was derived from the experimental electronic circular dichroism (ECD) spectrum using the Kramers-Kronig (KK) transform. The theoretical ORD spectra were calculated in the resonant region using linear response theory, and also using the KK transform of the theoretical ECD spectrum, at different theoretical levels, namely BHLYP/6-31G*, B3LYP/6-31G*, BLYP/6-31G*, and HF/6-31G*. Good agreement noted between experimental and predicted spectra allows for an unambiguous determination of the absolute configuration.