Triquinoline- versus Fullerene-Based Cycloparaphenylene Ionic Complexes: Comparison of Photoinduced Charge-Shift Reactions

A triquinoline cationic moiety (TQ?H⁺) has recently been designed as a novel molecular unit for supramolecular chemistry. In addition to some useful features, TQ?H⁺ has strong electron-acceptor properties, which renders the molecular cation a unique element in nanochemistry. TQ?H⁺ is found to form complexes with coronene (COR) and cycloparaphenylene (CPP). In this work, we report a computational study of photoinduced electron transfer in supramolecular complexes TQ?H⁺-COR, TQ?H⁺?12]CPP and (TQ?H⁺-COR)?12]CPP. The electron-transfer rates are estimated by using the semi-classical approach. The results are compared with the data previously obtained for a structurally similar inclusion complex Li⁺@C₆₀?10]CPP. In particular, we found a red solvatochromic shift for charge-shift bands in the TQ?H⁺-complexes unlike a blueshift showed by Li⁺@C₆₀?10]CPP. This distinction is explored in terms of electronic and structural features of the systems.