title: Photophysical Properties and Electronic Structure of Chlorin-Imides: Bridging the Gap between Chlorins and Bacteriochlorins.
abstract: Efficient light harvesting for molecular-based solar-conversion systems requires absorbers that span the photon-rich red and near-infrared (NIR) regions of the solar spectrum. Reported herein are the photophysical properties of a set of six chlorin-imides and nine synthetic chlorin analogues that extend the absorption deeper (624-714 nm) into these key spectral regions. These absorbers help bridge the gap between typical chlorins and bacteriochlorins. The new compounds have high fluorescence quantum yields (0.15-0.34) and long singlet excited-state lifetimes (4.2-10.9 ns). The bathochromic shift in Qy absorption is driven by substituent-based stabilization of the lowest unoccupied molecular orbital, with the largest shifts for chlorins that bear an electron-withdrawing, conjugative group at the 3-position in combination with a 13,15-imide ring.
authors.affiliation: †Department of Chemistry, Washington University, St. Louis, Missouri 63130-4889, United States.
authors.forename: Kaitlyn M
authors.initials: KM
authors.lastname: Faries
authors.affiliation: ‡Department of Chemistry, University of California, Riverside, Riverside, California 92521-0403, United States.
authors.forename: James R
authors.initials: JR
authors.lastname: Diers
authors.affiliation: †Department of Chemistry, Washington University, St. Louis, Missouri 63130-4889, United States.
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Springer
authors.affiliation: †Department of Chemistry, Washington University, St. Louis, Missouri 63130-4889, United States.
authors.forename: Eunkyung
authors.initials: E
authors.lastname: Yang
authors.affiliation: §Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States.
authors.forename: Marcin
authors.initials: M
authors.lastname: Ptaszek
authors.affiliation: §Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States.
authors.forename: Dorothée
authors.initials: D
authors.lastname: Lahaye
authors.affiliation: §Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States.
authors.forename: Michael
authors.initials: M
authors.lastname: Krayer
authors.affiliation: §Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States.
authors.forename: Masahiko
authors.initials: M
authors.lastname: Taniguchi
authors.affiliation: †Department of Chemistry, Washington University, St. Louis, Missouri 63130-4889, United States.
authors.forename: Christine
authors.initials: C
authors.lastname: Kirmaier
authors.affiliation: §Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States.
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Lindsey
authors.affiliation: ‡Department of Chemistry, University of California, Riverside, Riverside, California 92521-0403, United States.
authors.forename: David F
authors.initials: DF
authors.lastname: Bocian
authors.affiliation: †Department of Chemistry, Washington University, St. Louis, Missouri 63130-4889, United States.
authors.forename: Dewey
authors.initials: D
authors.lastname: Holten
mesh_terms: D004583:Electrons; D005453:Fluorescence; D007094:Imides / Q000737:chemistry*; D015394:Molecular Structure; D055668:Photochemical Processes; D011166:Porphyrins / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D007094:Imides; D011166:Porphyrins; C452433:bacteriochlorin; C006969:chlorin