Electron Transfer in Li+-doped Zn-porphyrin-[10]CPP⊃Fullerene Junction: Charge-separated Bands with Opposite Response to Polar Environment

Abstract

Recently synthesized porphyrin-cycloparaphenylene (ZnP-[10]CPP) junction is a powerful platform to develop useful organic photovoltaic devices. In this work, we computationally study photoinduced electron transfer processes in the supramolecular complex ZnP-[10]CPP⊃C60 and its Li+-doped derivative. The most striking finding is charge separation (CS) bands in ZnP-[10]CPP⊃Li+@C60 with opposite responses to solvent polarity. Besides CS that demonstrate a bathochromic shift, there exist CS transitions showing a rarely observed hypsochromic shift. The rates of energy transfer, electron transfer, and charge recombination in the supramolecular complexes are computed by using the semi-classical approach. These estimates suggest that the both types of CS states can be efficiently populated in polar media by decay of locally excited states