Vibronic structure and coupling of higher excited electronic states in carotenoids

► We analyze the UV absorption and Stark spectra of three carotenoids at low temperature. ► 1Ag+ band is induced by thermal deformations of the conjugated chain. ► The nBu state is comprised of two vibronically coupled electronic transitions. ► Stark spectrum indicates the Fano effect in the nBu state due to the electric field.