Journal ArticleExcited Charge Separation in a π-Interacting Phenothiazine–Zinc Porphyrin–Fullerene Donor–Acceptor ConjugateYadagiri, B [Academy of Scientific and Innovative Research, CSIR-IICT, Tarnaka, Hyderabad 500007, India]; Kaswan, Ram Ratan [Department of Chemistry, University of North Texas, 1155 Union Circle, #305070, Denton, Texas 76203-5017, United States]; Tagare, Jairam [Department of Polymers and Functional Materials, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500007, India]; Kumar, Vinay [Academy of Scientific and Innovative Research, CSIR-IICT, Tarnaka, Hyderabad 500007, India]; Rajesh, Manne Naga [Academy of Scientific and Innovative Research, CSIR-IICT, Tarnaka, Hyderabad 500007, India]; Singh, Surya Prakash [Academy of Scientific and Innovative Research, CSIR-IICT, Tarnaka, Hyderabad 500007, India] (ORCID:0000000156707329); Karr, Paul A [Department of Physical Sciences and Mathematics, Wayne State College, 111 Main Street, Wayne, Nebraska 68787, United States]; D’Souza, Francis [Department of Chemistry, University of North Texas, 1155 Union Circle, #305070, Denton, Texas 76203-5017, United States] (ORCID:0000000338158949); Giribabu, Lingamallu [Academy of Scientific and Innovative Research, CSIR-IICT, Tarnaka, Hyderabad 500007, India] (ORCID:0000000159367729)Shea, JEA zinc phthalocyanine-pyrroloperylenediimide dyad connected through a nitrogen heteroatom (PDI-N-ZnPc) has been newly synthesized and characterized. Solvent polarity-dependent singlet-singlet energy transfer and electron transfer quenching were envisioned from absorption and steady-state fluorescence studies. Electrochemical and spectroelectrochemical studies enabled the assessment of the redox potential of the donor and acceptor entities, as well as the spectral characterization of the one-electron oxidation and reduction products. DFT studies were performed to investigate the geometry and electronic structure, as well as the role of N-connectivity in determining the relative orientation of the entities. Further, time-dependent DFT studies helped establish the different excited states responsible for promoting charge separation. An energy diagram was subsequently established to visualize different photo-physical events. Finally, femtosecond transient absorption spectral studies were performed in both nonpolar and polar solvents to observe energy and electron transfer events. The kinetic data were subsequently analyzed using global and target analyses. The persistence of the charge-separated state in the present dyad, compared with earlier reported ZnPc-PDI dyads featuring carbon-carbon connectivity, was the primary outcome of the present study, highlighting the role of heteroatom linkage in regulating electron transfer dynamics in donor-acceptor conjugates.ACS2024-05-3010673200The Journal of Physical Chemistry A128214233 to 42411089-5639https://doi.org/10.1021/acs.jpca.4c009762345836National Science Foundation