Viscosity and temperature dependence of the magnetic isotope effect
نویسندگان
چکیده
The 13C enrichment observed in the first order photolytic decomposition of dibenzylketone (1,3-diphenyl2-propanone) was studied as a function of solvent viscosity and temperature. The isotope effect is due to electron-nuclear hyperfine interactions in the free radical intermediates of the reaction. The results are explained using a continuum diffusion model and a simplified version of the radical pair theory of Chemically Induced Dynamic Nuclear Polarization (CIDNP). The isotope effect is substantially enhanced at intermediate values of viscosity.
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