论文信息 - The Occurrence of a D–D Mechanism in the Ethanol Solution of Eosine

The Occurrence of a D–D Mechanism in the Ethanol Solution of Eosine

The occurrence of a D–D mechanism in which the photochemical reaction is initiated by the interaction of the triplet dye and the ground-state dye molecules, has been established for the ethanol solution of eosine. Chief evidence for it has been afforded by: 1) the predominance of the second-order reaction at high dye concentrations, 2) the dependence of the quantum yield of the photoreduction upon the dye concentration, and 3) the effect of the dye concentration on the photochemical oxygen absorption and on the oxydative photobleaching of dye. Assuming no simple deactivation between the triplet dye and allylthiourea, the quantum yield for the formation of the triplet dye has been evaluated as 0.056. Then the rate constants for the following elementary reactions, (Remark: Graphics omitted.) and DT+ATU→intermediate are, respectively, 1×108 M−1sec−1 and 1–2×105 M−1sec−1. It seems that the reaction between oxygen and the triplet dye is chiefly an eventual deactivation of the latter, with no appreciable decomp...

NemotoMasae | UsuiYoshiharu | KoizumiMasao

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