MARY-detected ESR spectra of radical ions in liquid solutions for systems with crossing Zeeman levels

Magnetic field modulation of the delayed fluorescenceyield in the photoionization reaction of N, N, N′, N′‐tetramethyl‐p‐phenylenediamine in water

“…In contrast to the previous reports [5,7], the MFE on the delayed fluorescence [8] can only be explained if the singlet RIP is more reactive than the triplet one. In the present study we report on the MFE on the delayed fluorescence from TMPPD in water and water/DMSO mixture using modulation technique [9][10]. This technique enables the characterization of the RIP observed and allows the registration of its lifetime.…”

“…In some cases however the RIP's lifetime is long enough for effective spin mixings but the detection methods are too slow to register or/and insensitive to very small variations accompanying these spin mixings. Introduction of the modulation technique to the methods of detection of MFEs introduced much better signal-to-noise ratio and higher time resolution to the detection of radical pairs in solution [9,10,12]. MARY (MAgnetic field modulation of the Reaction Yield) spectra, or more precisely the MFEs on the recombination fluorescence yield, exhibit relatively narrow lines.…”

Simple rules for resolved level-crossing spectra in magnetic field effects on reaction yields

“…Although so far the only experimental observations of the ESR structure using this approach have been the "spectrum" at 3a for an unresolved inhomogeneous spectrum as a proof of principle in Tadjikov et al (1996) and arguments based on the lack of the inhomogeneous spectrum at 3a in several works on radiation chemistry (Tadjikov et al, 1997;Usov et al, 1997;Sviridenko et al, 1998) from just one group, we hope that the current surge of interest to the level (anti)crossing interpretation of magnetic resonance will draw attention to this aspect of the humble magnetic field effect experiments.…”

Magnetic Field Effects on Radical Pairs in Homogeneous Solution

“…[63][64][65][66][67] For many RPs generated using radiolysis, crossings of energy levels during the move from zero to normal field can bring about specific resonances due to level crossings of the various RP spin states, which in ideal cases can be observed as peaks in the MARY spectrum. Early experiments only showed such resonances in RPs with degenerate HFCs, 63 but recent work has revealed experimentally observable resonances even in RPs with nondegenerate couplings.…”