Optical properties of supramolecular complexes coupled to a metal-nanoparticle: A computational study

►Computation of absorption and emission spectra of supramolecular complexes (SC). ► Coupling to a metal nanoparticle (MNP) let become dark exciton levels visible. ► Emission spectra display a SC-MNP coupling dependent line-shift. ► Direct evidence for a MNP-induced electron-vibrational level renormalization.