Computational studies of charge transfer in organic solar photovoltaic cells: A review

• Charge transfer excitations in porphyrin–fullerene complexes have been reviewed.
• An overview of quantum chemical methods relevant to describe charge transfer excitations is provided.
• Description of important factors that influence photophysical properties of porphyrin–fullerene complexes is given.

Photoinduced charge transfer (CT) is a fundamental process that determines the overall energy conversion efficiency of organic solar photovoltaic cells (OPVs). This review focuses on the advantages and pitfalls of theoretical/computational methods available to describe CT excitations in donor–acceptor (D–A) complexes. Studies of porphyrin–fullerene constructs as model D–A systems will be used to illustrate progress in this area.