title: Spectroscopic Investigation of the Carotenoid Deoxyperidinin: Direct Observation of the Forbidden S0 → S1 Transition.
abstract: This paper presents a spectroscopic investigation of deoxyperidinin, a synthetic peridinin analogue in which the carbonyl functional group in peridinin was replaced by a nonconjugated methylene group. Steady-state and ultrafast time-resolved absorption and fluorescence spectroscopic experiments are carried out on deoxyperidinin in n-hexane and acetonitrile at room temperature and in 2-methyltetrahydrofuran at 77 K. The spectra of deoxyperidinin have higher vibronic resolution compared to those of peridinin. The higher resolution is due to a substantial reduction in both molecular conformational disorder and inhomogeneous broadening of the spectra of deoxyperidinin compared to peridinin. Features in the steady-state absorption spectrum of deoxyperidinin that are not evident in the spectrum of peridinin are unambiguously assigned to the forbidden S0 (1(1)Ag(-)) → S1 (2(1)Ag(-)) absorption transition. The characteristics of both the steady-state and time-resolved spectra are interpreted using EOM-CCSD, SAC-CI, and MNDO-PSDCI quantum computational formalisms that provided a theoretical framework for understanding the photophysical properties of the molecules.
authors.affiliation: Department of Chemistry, University of Connecticut , 55 North Eagleville Road, Storrs, Connecticut 06269-3060, United States.
authors.forename: Jordan A
authors.initials: JA
authors.lastname: Greco
authors.affiliation: Department of Chemistry, University of Connecticut , 55 North Eagleville Road, Storrs, Connecticut 06269-3060, United States.
authors.forename: Amy M
authors.initials: AM
authors.lastname: LaFountain
authors.affiliation: Graduate School of Science, Osaka City University , 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.
authors.forename: Naoto
authors.initials: N
authors.lastname: Kinashi
authors.affiliation: Graduate School of Science, Osaka City University , 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Shinada
authors.affiliation: Graduate School of Science, Osaka City University , 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Sakaguchi
authors.affiliation: Graduate School of Science, Osaka City University , 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Katsumura
authors.affiliation: Department of Biology, Washington University in Saint Louis , One Brookings Drive, St. Louis, Missouri 63130, United States.
authors.forename: Nikki Cecil M
authors.initials: NC
authors.lastname: Magdaong
authors.affiliation: Photosynthetic Antenna Research Center, Washington University in Saint Louis , One Brookings Drive, St. Louis, Missouri 63130, United States.
authors.forename: Dariusz M
authors.initials: DM
authors.lastname: Niedzwiedzki
authors.affiliation: Department of Chemistry, University of Connecticut , 55 North Eagleville Road, Storrs, Connecticut 06269-3060, United States.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Birge
authors.affiliation: Department of Chemistry, University of Connecticut , 55 North Eagleville Road, Storrs, Connecticut 06269-3060, United States.
authors.forename: Harry A
authors.initials: HA
authors.lastname: Frank
mesh_terms: D002338:Carotenoids / Q000737:chemistry*; D011789:Quantum Theory; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: C016040:peridinin; D002338:Carotenoids