![]() ![]() The photophysical and photochemical properties of several aromatic ketones are strongly influenced by the energy and configuration of their electronically excited state. 10 9 L mol -1 s -1 para fenol e seus derivados contendo substituintes poleres, bem como para indol, trietilamina e DABCO. As constantes de velocidade de supressão para o triplete de tioxantona, k q, variaram de (1,7 ± 0,1) × 10 6 L mol -1 s -1 para tolueno a ca. Quando foram utilizados solventes doadores de hidrogênio, foi observado o surgimento de uma nova banda no espectro de absorção para os transientes, com máximo a 410 nm, a qual foi atribuída ao radical cetila derivado da tioxantona. O máximo do comprimento de onda de absorção e o tempo de vida para o seu estado excitado triplete são dependetes do solvente. Keywords: laser flash photolysis, tioxanthone, triplet excited state, solvent effectĪ fotorreatividade do estado excitado triplete de tioxantona (TX) foi investigada empregando a técnica de fotólise por pulso de laser. 10 9 L mol -1 s -1 for phenol and its derivatives containing polar substituents, as well as for indole, triethylamine and DABCO. Quenching rate constants, k q, ranged from (1.7 ± 0.1) × 10 6 L mol -1 s -1 for toluene to ca. When hydrogen donor solvents were employed, a new band at 410 nm was observed in the triplet absorption spectrum, which was attributed to the ketyl radical derived from thioxantone. The wavelength for the absorption maximum and the lifetime of the triplet excited state are solvent dependent. The photoreactivity of the triplet excited state of thioxanthone (TX) was investigated employing the laser flash photolysis technique. IIInstituto de Química, Universidade Federal da Bahia, Campus de Ondina, 40170-290 Salvador-BA, Brazil Rodrigues I Francisco de Assis da Silva I José Carlos Netto-Ferreira I,II, * de Química, Universidade Federal Rural do Rio de Janeiro, BR 465 km 7, 23970-000 Seropédica-RJ, Brazil Laser flash photolysis study of the photochemistry of thioxanthone in organic solvents ![]()
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