Atomistic models based on quantum-chemical calculations are combined with time-resolved spectroscopicinvestigations to explore the migration of electronic excitations along oligophenylenevinylene-based chiralstacks. It is found that the usual Pauli master equation (PME) approach relying on uncoherent transport betweenindividual chromophores underestimates the excitation diffusion dynamics, monitored here by the time decayof the transient polarization anisotropy. A better agreement to experiment is achieved when accounting forexcitation delocalization among acceptor molecules, as implemented in a modified version of the PME model.The same models are applied to study light harvesting and trapping in guest−host systems built from oligomersof different lengths.
