Kang, Hyun SukSatraitis, AndriusMeares, AdamBhagavathy, Ganga ViswanathanDiers, James R.Niedzwiedzki, Dariusz M.Kirmaier, ChristinePtaszek, MarcinBocian, David F.Holten, Dewey2022-07-142022-07-142021-04-20Kang, Hyun Suk et al. Conjugated-linker dependence of the photophysical properties and electronic structure of chlorin dyads.Journal of Porphyrins and Phthalocyanines 25, No. 07 (2021): 639-663. https://www.worldscientific.com/doi/10.1142/S1088424621500620https://doi.org/10.1142/S1088424621500620http://hdl.handle.net/11603/25152The synthesis, photophysical properties and electronic structure of seven new chlorin dyads and associated benchmark monomers are described. Each dyad contains two identical chlorins linked at the macrocycle β-pyrrole 13-position. The extent of electronic communication between chlorin constituents depends on the nature of the conjugated linker. The communication is assessed by modification of prominent ground-state absorption and redox properties, rate constants and yields of excited-state decay processes, and molecular-orbital characteristics. Relative to the benchmark monomers, the chlorin dyads in toluene exhibit a substantial bathochromic shift of the long-wavelength absorption band (30 nm average), two-fold increased radiative rate constant [average (10 ns)−1vs. (22 ns)−1], reduced singlet excited-state lifetimes (average 5.0 ns vs. 8.2 ns), and increased fluorescence quantum yields (average 0.56 vs. 0.42). The excited-state lifetime and fluorescence yield for the chlorin dyad with a benzothiadiazole linker are reduced substantially in benzonitrile vs. toluene due largely to ∼25-fold accelerated internal conversion. The results aid design strategies for molecular architectures that may find utility in solar-energy conversion and photomedicine.73 pagesen-USElectronic version of an article published as Journal of Porphyrins and Phthalocyanines 25, No. 07, 2021, 639-663 https://doi.org/10.1142/S1088424621500620 © [copyright World Scientific Publishing Company] https://www.worldscientific.com/doi/pdf/10.1142/S1088424621500620Text