MANIFESTATION OF QUANTUM COHERENCE UPON RECOMBINATION OF RADICAL-ION PAIRS IN WEAK MAGNETIC-FIELDS - SYSTEMS WITH EQUIVALENT NUCLEI

Magnetosensitive radiofluorescence has been used to study the magnetic field effect at fields of the order of hyperfine ones during the reco mbination of spin-correlated radical ion pairs in non-polar solutions. For radical pairs, in which hyperfine interactions are essential only for equivalent nuclei in one of the pair partners, additional local m axima of fluorescence intensity in characteristic 'multiple' fields we re observed. These maxima arise from the coherent nature of the radica l pair initial state: different stationary states interfere in the fie lds where energy levels of the radical pair cross.