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Published on: July 19, 2019
Magnetic isotope effect in the photolysis of organotin compounds
Anatoly L Buchachenko1, Vladimir L Ivanov, Vitaly A Roznyatovsky
1Chemical Department of M. V. Lomonosov Moscow State University, Moscow 119992, Russia. abuchach@chph.ras.ru
Abstract:
Photolysis of organotin molecules RSnMe3 is shown to be a spin selective radical reaction accompanied by fractionation of magnetic, (117,119)Sn, and nonmagnetic, (118,120)Sn, isotopes between starting reagents and products. A primary photolysis process is a homolytic cleavage of the C-Sn bond and generation of a triplet radical pair as a spin-selective nanoreactor. Nuclear spin dependent triplet-singlet conversion of the pair results in the tin isotope fractionation. Experimentally detected isotope distribution unambiguously demonstrates that the classical, mass-dependent isotope effect is negligible in comparison with magnetic, spin-dependent isotope effect.
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