TY - JOUR

T1 - Unexpectedly Large Spin Coherence Effects in the Recombination Fluorescence from Irradiated Highly Polar Solutions on a Nanosecond Time Scale

AU - Borovkov, Vsevolod I.

PY - 2017/10/12

Y1 - 2017/10/12

N2 - Spin correlation effects in the geminate recombination of radical ion pairs in irradiated highly polar liquids are typically believed to be negligible due to a high escape probability for the ions. This report presents the results of an exploratory study of organic polar solvents aimed at the searching for, and estimating the magnitude of, the time-resolved magnetic field effects (TR MFEs) in the delayed radiation-induced fluorescence from diluted solutions of a luminophore. It has been found that upon the high-energy irradiation of the solutions in polar liquids, such as dichloroethane (ε ≈ 10), methanol (ε ≈ 33), acetonitrile (ε ≈ 37), dimethylformamide (ε ≈ 37), dimethyl sulfoxide (ε ≈ 47), ethylene carbonate (ε ≈ 89), substantial spin coherence effects in the delayed fluorescence can be observed within a time range up to ∼100 ns. In most of the cases studied, magnetic resonance characteristics of primary or very early solvent-related radical ions were evaluated from the TR MFE curves. This approach can, therefore, be widely used to complement results obtained by the pulse radiolysis technique with structural and kinetic data extracted from the magnetic resonance characteristics of the short-lived radical ions formed in irradiated media.

AB - Spin correlation effects in the geminate recombination of radical ion pairs in irradiated highly polar liquids are typically believed to be negligible due to a high escape probability for the ions. This report presents the results of an exploratory study of organic polar solvents aimed at the searching for, and estimating the magnitude of, the time-resolved magnetic field effects (TR MFEs) in the delayed radiation-induced fluorescence from diluted solutions of a luminophore. It has been found that upon the high-energy irradiation of the solutions in polar liquids, such as dichloroethane (ε ≈ 10), methanol (ε ≈ 33), acetonitrile (ε ≈ 37), dimethylformamide (ε ≈ 37), dimethyl sulfoxide (ε ≈ 47), ethylene carbonate (ε ≈ 89), substantial spin coherence effects in the delayed fluorescence can be observed within a time range up to ∼100 ns. In most of the cases studied, magnetic resonance characteristics of primary or very early solvent-related radical ions were evaluated from the TR MFE curves. This approach can, therefore, be widely used to complement results obtained by the pulse radiolysis technique with structural and kinetic data extracted from the magnetic resonance characteristics of the short-lived radical ions formed in irradiated media.

KW - LI-ION BATTERIES

KW - RADICAL CATIONS

KW - ELECTRON LOCALIZATION

KW - LIQUID ACETONITRILE

KW - MAGNETIC-FIELDS

KW - RESONANCE

KW - ANIONS

KW - RADIATION

KW - PAIRS

UR - http://www.scopus.com/inward/record.url?scp=85031325898&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcb.7b08813

DO - 10.1021/acs.jpcb.7b08813

M3 - Article

C2 - 28915031

AN - SCOPUS:85031325898

VL - 121

SP - 9422

EP - 9428

JO - Journal of Physical Chemistry B

JF - Journal of Physical Chemistry B

SN - 1520-6106

IS - 40

ER -