Intramolecular Charge Transfer
Mostrando 1-12 de 19 artigos, teses e dissertações.
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1. A Water Soluble Naphthalimide-Based Chemosensor for Fluorescent Detection CN- in Pure Water and Its Application in Practical Samples
By rationally introducing aromatic carboxyl functionalized 1,8-naphthalimide, a water soluble fluorescent chemosensor (DA) was successfully synthesized. It could selectively and sensitively detect CN- in pure water via an intramolecular charge transfer to twisted intramolecular charge transfer (ICT-TICT) state change mechanism. The detection limit of the che
J. Braz. Chem. Soc.. Publicado em: 2018-07
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2. Synthesis, characterization and computational studies of (E)-2-{[(2-aminopyridin-3-yl)imino]-methyl}-4,6-di-tert-butylphenol
(E)-2-{[(2-Aminopyridin-3-yl)imino]-methyl}-4,6-di-tert-butyl-phenol ( 3: ), a ligand containing an intramolecular hydrogen bond, was prepared according to a previous literature report, with modifications, and was characterized by UV-vis, FTIR, ¹H-NMR, 13C-NMR, HHCOSY, TOCSY and cyclic voltammetry. Computational analyses at the level of DFT and TD-DFT were
Quím. Nova. Publicado em: 2014
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3. Modulating the electronic structure of amino acids: interaction of model lewis acids with anthranilic acid
On the basis of theoretical B3LYP calculations, Yáñez and co-workers (J. Chem. Theory Comput. 2012, 8, 2293) illustrated that beryllium ions are capable of significantly modulating (changing) the electronic structures of imidazole. In this computational organic chemistry study, the interaction of this β-amino acid and five model Lewis acids (BeF1+, Be2+,
Quím. Nova. Publicado em: 2014
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4. Preparação e estudo fotofísico de nanopartículas de sílica marcadas com compostos fluorescentes / Preparation and photophysical study of silica nanoparticles grafted with fluorescent compounds
Photophysical behavior of 9-aminoacridine (9AA) and derivatives, safranine O, auramine and 9-vinylanthracene was investigated, in silica particles. Firstly, commercial silica was modified and grafted with acridinic dyes; however, photophysical studies became unviable, due to its morphology. Silica nanospheres were prepared by Stöber method, with mean diamet
Publicado em: 2009
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5. Caracterização espectroscópica e por modelagem mecânico-quântica, de compostos com potencial aplicação em dispositivos ópticos não-lineares
In the present work, the compounds 1-(3,4,5-trimethoxiphenil)-2-(2- tienyl) -5-(4-nitrophenylazo) pirrol (compound 1) and 5-dicianovinyl-5- piperidine-5,2:5:2- tertiophene (compound 2), were characterized using a combination of spectroscopic measurements and quantum mechanical calculation, aiming to evaluate if they present the necessary requisites for appli
Publicado em: 2009
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6. SÃntese, caracterizaÃÃo e propriedades fotocrÃmicas da sais derivados do Ãcido N-(3,5-dinitrobenzoil)-α-fenilglicina
The preparation and characterization of salts derived from N-(3,5- dinitrobenzoyl)-α-phenylglycine was carried out by using protonated amines as counter-ion, as follows: NH4 + (DNBAm), (CH3-CH2-)2NH2 + (DNBD), (CH3-CH2-CH2- )NH3 + (DNBP), (CH3-CH2-CH2-CH2-)NH3 + (DNBBu) and (CH3-CH2-)3NH+ (DNBT). These salts showed photocromic effect with ultraviolet (U
Publicado em: 2008
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7. Fluorescence modulation of acridine and coumarin dyes by silver nanoparticles / Modulação de fluorescência de amino coumarinas e acridinas por nanopartículas de prata
Nanopartículas de prata foram preparadas pela redução química de íons prata (AgNO3) por borohidreto de sódio (NaBH4) na presença de poli-(N)-vinil-2-pirrolidona em solução de álcoois de cadeia curta. As nanopartículas de prata apresentaram maior estabilidade em 2- propanol, e o diâmetro aproximado das nanopartículas Ag0 obtidas neste solvente é
Publicado em: 2007
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8. Estrutura eletronica e polarizabilidades de betainas
This thesis is dedicated to a theoretical study of the electronic structure and optical properties of betaine molecules carried at the semiempirical and ab initio levels. The charge distribution, the dipole moment and the linear (a) and first nonlinear (Ã) polarizabilities of a total of 66 betaine molecules belonging to 6 different families were calculated.
Publicado em: 2007
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9. "Intramolecular charge and hydrogen bon transfer in 9-aminoacridine derivatives" / "Transferência de carga e ligação de hidrogênio intramolecular em derivados de 9-aminoacridina"
Neste trabalho, o corante 9-aminoacridina foi derivatizado com compostos vinílicos que possuem grupos retiradores de elétrons. A incorporação destes leva à mudanças nas propriedades fotofísicas dos derivados, tais como deslocamentos para regiões de menor energia nos espectros de absorção e emissão, sugerindo a presença de transferência de carga
Publicado em: 2006
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10. Synthesis and properties of new polymetalated porphyrins / Sintese e propriedades de novas porfirinas polimetaladas
Metalloporphyrins containing peripheral meta l complexes attached to the macrocyclic ring can exhibit an interesting supramolecular chemistry, modeling , for instance, photosynthetic systems in their ability to undergo intramolecular photocatalyzed electron transfer; and cytochrome-c oxidase , by acting as multielectron redox catalysts in the reduction of mo
Publicado em: 1989
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11. Interplay between excited-state intramolecular proton transfer and charge transfer in flavonols and their use as protein-binding-site fluorescence probes.
A comparative study is presented of competitive fluorescences of three flavonols, 3-hydroxyflavone, 3,3',4',7-tetrahydroxyflavone (fisetin), and 4'-diethylamino-3-hydroxyflavone (DHF). The normal fluorescence S1-->S0 (400-nm region) is largely replaced by the proton-transfer tautomer fluorescence S'1-->S'0 in the 550-nm region for all three of the flavonols
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12. Carotenoid to chlorophyll energy transfer in the peridinin–chlorophyll-a–protein complex involves an intramolecular charge transfer state
Carotenoids are, along with chlorophylls, crucial pigments involved in light-harvesting processes in photosynthetic organisms. Details of carotenoid to chlorophyll energy transfer mechanisms and their dependence on structural variability of carotenoids are as yet poorly understood. Here, we employ femtosecond transient absorption spectroscopy to reveal energ
National Academy of Sciences.