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Migration of Excitation Energy in Furocoumarins.

ABSTRACT: The migration of excitation energy of a number of psoralen compounds has been studied. For this, the methods of induced absorption spectroscopy, stationary electron spectroscopy, fluorescence and phosphorescence, as well as quantum chemistry were used. A comparative photostability of psoralen was achieved by exposure to a XeCl excilamp irradiation (emission wavelength λ_em = 308 nm) with parameters Δλ = 5-10 nm, W_peak = 18 mW/cm², p = 8.1 J/cm³, f = 200 kHz, pulse duration 1 μs. It was found that the singlet-triplet transition played a major role in the migration of excitation energy into triplet states. Among all tested compounds, substances with an OCH₃-group in the structure have the strongest effect on the spectral-luminescent characteristics.

SUBMITTER: Tchaikovskaya ON

PROVIDER: S-EPMC8600316 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Migration of Excitation Energy in Furocoumarins.

Tchaikovskaya O N ON Dmitrieva N G NG Bocharnikova E N EN Chaidonova V S VS Avramov P V PV

Frontiers in chemistry 20211104

The migration of excitation energy of a number of psoralen compounds has been studied. For this, the methods of induced absorption spectroscopy, stationary electron spectroscopy, fluorescence and phosphorescence, as well as quantum chemistry were used. A comparative photostability of psoralen was achieved by exposure to a XeCl excilamp irradiation (emission wavelength λem = 308 nm) with parameters Δλ = 5-10 nm, Wpeak = 18 mW/cm2, p = 8.1 J/cm3, ...[more]

PMID: 34805093

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