Open AccessОпределение констант скоростей и механизма фотопревращений металлопорфиринов методом решения обратной фотокинетической задачи
Author(s) -
И.В. Станишевский,
С.М. Арабей
Publication year - 2021
Publication title -
optika i spektroskopiâ
Language(s) - English
Resource type - Journals
eISSN - 2782-6694
pISSN - 0030-4034
DOI - 10.21883/os.2021.02.50552.180-20
Subject(s) - kinetic energy , kinetics , excited state , excitation , monotonic function , inverse , interpretation (philosophy) , thermodynamics , fluorescence , chemistry , reaction rate constant , materials science , analytical chemistry (journal) , physics , atomic physics , mathematics , mathematical analysis , computer science , optics , quantum mechanics , chromatography , geometry , programming language
The fluorescence kinetics of some substituted Zn- and Mg-porphyrins in solid polymer films upon excitation by two-step-wise rectangular laser pulses and 293 K were investigated by the inverse kinetic problem methods. The experimental non-monotonic kinetic curves were approximated by the simulated ones within the framework of a six-level energy scheme describing the reversible interconversions between the two complexes. The best fit between the experimental and simulated curves was obtained by iterative optimization using the Nelder-Mead algorithm. Based on the statistically estimated values of the rate constants and parameters of the considered models, an interpretation of the observed kinetics was given and the conclusion drawn that the interconversions are caused by the process of reversible extra-liganding of the central metal ion, which occurs in the excited triplet T 1 state.