Browsing CHEM Faculty Scholarship by Author "Ohkubo, Kei"
Now showing items 1-9 of 9
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Anion-complexation-induced stabilization of charge separation
D'Souza, Francis; Subbaiyan, Navaneetha K.; Xie, Yongshu; Hill, Jonathan P.; Ariga, Katsuhiko; Ohkubo, Kei; Fukuzumi, Shunichi (American Chemical Society, 2009-11-11)A supramolecular oligochromophoric system possessing exclusive binding sites for both a guest electron acceptor and an anionic cofactor species is developed, and anion-binding-induced stabilization of the charge-separated ... -
Bisdonor-azaBODIPY-fullerene supramolecules: syntheses, characterization, and light-Induced electron-transfer studies
Bandi, Venugopal; El-Khouly, Mohamed E.; Ohkubo, Kei; Nesterov, Vladimir N.; Zandler, Melvin E.; Fukuzumi, Shunichi; D'Souza, Francis (American Chemical Society, 2014-02-06)Achieving ultrafast light-induced charge separation requires carefully selected donor and acceptor entities often held together in a closer proximity. In the present investigation, two tetrads featuring a near-IR-emitting ... -
Corrole-fullerene dyads: formation of long-lived charge-separated states in nonpolar solvents
D'Souza, Francis; Chitta, Raghu; Ohkubo, Kei; Tasior, Mariusz; Subbaiyan, Navaneetha K.; Zandler, Melvin E.; Rogacki, Maciek K.; Gryko, Daniel T.; Fukuzumi, Shunichi (American Chemical Society, 2008-10-29)The first example of covalently linked free-base corrole-fullerene dyads is reported. In the newly synthesized dyads, the free-energy calculations performed by employing the redox and singlet excited-state energy in both ... -
Excitation-wavelength-dependent, ultrafast photoinduced electron transfer in bisferrocene/bf2-chelated-azadipyrromethene/fullerene tetrads
Bandi, Venugopal; El-Khouly, Mohamed E.; Ohkubo, Kei; Nesterov, Vladimir N.; Zandler, Melvin E.; Fukuzumi, Shunichi; D'Souza, Francis (John Wiley and Sons, 2013-05-27)Donor–acceptor distance, orientation, and photoexcitation wavelength are key factors in governing the efficiency and mechanism of electron-transfer reactions both in natural and synthetic systems. Although distance and ... -
Face-to-face pacman-type porphyrin-fullerene dyads: design, synthesis, charge-transfer interactions, and photophysical studies
D'Souza, Francis; Maligaspe, Eranda; Karr, Paul A.; Schumacher, Amy Lea; El Ojaimi, Maya; Gros, Claude P.; Barbe, Jean-Michel; Ohkubo, Kei; Fukuzumi, Shunichi (John Wiley and Sons, 2008-01-01)Pacman-type face-to-face zinc-porphyrin-fullerene dyads have been newly synthesized and studied. Owing to the close proximity of the donor and acceptor entities, strong pi-pi intramolecular interactions between the porphyrin ... -
Metal quinolinolate-fullerene(s) donor-acceptor complexes: evidence for organic LED molecules acting as electron donors in photoinduced electron-transfer reactions
D'Souza, Francis; Maligaspe, Eranda; Zandler, Melvin E.; Subbaiyan, Navaneetha K.; Ohkubo, Kei; Fukuzumi, Shunichi (American Chemical Society, 2008-12-17)Tris(quinolinolate)aluminum(III) (AlQ3) is the most widely used molecule in organic light-emitting devices. There exists a strong demand for understanding the photochemical and photophysical events originating from this ... -
Photochemical charge separation in closely positioned donor-boron dipyrrin-fullerene triads
Wijesinghe, Channa A.; El-Khouly, Mohamed E.; Subbaiyan, Navaneetha K.; Supur, Mustafa; Zandler, Melvin E.; Ohkubo, Kei; Fukuzumi, Shunichi; D'Souza, Francis (John Wiley and Sons, 2011-02-14)A series of molecular triads, composed of closely positioned boron dipyrrin-fullerene units, covalently linked to either an electron donor (donor(1) -acceptor(1) -acceptor(2) -type triads) or an energy donor (antenna-donor(1) ... -
Photosynthetic reaction center mimicry: low reorganization energy driven charge stabilization in self-assembled cofacial zinc phthalocyanine dimer-fullerene conjugate
D'Souza, Francis; Maligaspe, Eranda; Ohkubo, Kei; Zandler, Melvin E.; Subbaiyan, Navaneetha K.; Fukuzumi, Shunichi (American Chemical Society, 2009-07-01)By employing well-defined self-assembly methods, a biomimetic bacterial photosynthetic reaction center complex has been constructed, and photoinduced electron transfer originating in this supramolecular donor-acceptor ... -
Review -- Two different multiple photosynthetic reaction centers using either zinc porphyrinic oligopeptide-fulleropyrrolidine or free-base porphyrinic polypeptide-Li+@C60supramolecular complexes
Solladie, Nathalie; Fukuzumi, Shunichi; Ohkubo, Kei; D'Souza, Francis; Rein, Regis; Saito, Kenji; Troiani, Vincent; Qiu, Hongjin; Gadde, Suresh; Hasegawa, Tetsuya (Institute of Physics Publishing, 2020-08-10)An overview of two successful examples of photosynthetic reaction center models combined with light-capturing antenna chromophores is presented. In the first example, supramolecular complexes are formed between flexible ...