A compact model system for electron-phonon calculations in discotic materials

Electron-phonon coupling underlies the unwanted rapid relaxation of electrically excited states in potential organic solar-cell materials. A compact model for the vibrational dynamics of 2,3,6,7,10,11-hexakishexyloxytriphenylene (HAT6) is derived from the combined use of inelastic neutron scattering (INS) spectroscopy and first-principles calculations. Because this model reproduces the essential features of the vibrational dynamics and electronic structure on the aromatic core of HAT6 it can be used as a basis for future calculations of the relaxation mechanisms of the electronically excited states.