TY - JOUR

T1 - Primary radical ions in irradiated carbonates

AU - Tretyakova, Irina S.

AU - Borovkov, Vsevolod I.

N1 - Финансирующий спонсор Номер финансирования Акроним Ministry of Science and Higher Education of the Russian Federation FWGF-2021-0003,121032500067-9

PY - 2025

Y1 - 2025

N2 - This study focuses on primary radical ionic species created in liquid carbonates upon high-energy radiation. We studied the radiation-induced fluorescence intensity decays observed from solutions of luminophores in dimethyl, diethyl, ethylene, and propylene carbonates. Based on the effects of external magnetic and electric fields on the fluorescence decays on a timescale of 1–60 ns and quantum chemical calculations, we found that in all studied carbonates, solvent ionization was rapidly followed by the formation of comparatively long-lived positive charge and unpaired electron spin carriers. These carriers are complexes in which two carbonate molecules are oriented to each other by carbonyl groups, with the charge and spin density primarily distributed over these two C==O groups. In the case of diethyl carbonate, the formation of such a complex occurs with a probability that depends on the conformation of ionized molecules and on the rate of parallel reaction of intramolecular proton transfer from the methyl or methylene groups to the carbonyl oxygen atom. In low-polarity carbonates, evidence for the existence of solvent radical anions with molecular mobility was found..

AB - This study focuses on primary radical ionic species created in liquid carbonates upon high-energy radiation. We studied the radiation-induced fluorescence intensity decays observed from solutions of luminophores in dimethyl, diethyl, ethylene, and propylene carbonates. Based on the effects of external magnetic and electric fields on the fluorescence decays on a timescale of 1–60 ns and quantum chemical calculations, we found that in all studied carbonates, solvent ionization was rapidly followed by the formation of comparatively long-lived positive charge and unpaired electron spin carriers. These carriers are complexes in which two carbonate molecules are oriented to each other by carbonyl groups, with the charge and spin density primarily distributed over these two C==O groups. In the case of diethyl carbonate, the formation of such a complex occurs with a probability that depends on the conformation of ionized molecules and on the rate of parallel reaction of intramolecular proton transfer from the methyl or methylene groups to the carbonyl oxygen atom. In low-polarity carbonates, evidence for the existence of solvent radical anions with molecular mobility was found..

UR - https://www.mendeley.com/catalogue/be58d64d-392d-3242-a324-7359c4b5028d/

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-105000156095&origin=inward&txGid=b3d8f181c5e941dd7202739fb0001382

U2 - 10.1039/d5cp00263j

DO - 10.1039/d5cp00263j

M3 - Article

C2 - 40067343

JO - Physical Chemistry Chemical Physics

JF - Physical Chemistry Chemical Physics

SN - 1463-9076

ER -