Enrichment of Germanium-73 with the Magnetic Isotope Effect on the Hydrogen Abstraction Reaction of Triplet Benzophenone with Triethylgermane in an SDS Micellar Solution

Using the hydrogen abstraction reaction of triplet benzophenone with triethylgermane in an SDS micellar solution, we succeeded in enriching 73Ge with the magnetic isotope effect. At zero magnetic field, 0.5% enrichment of 73Ge was observed for the cage product (diphenyl(triethylgermyl)methanol). With increasing magnetic field strength (B), the enrichment of 73Ge increased initially, attaining the maximum value of 5.3% at 500 G. At higher fields (500 G < B ≤ 10 kG), it decreased gradually, becoming 1.0% at 10 kG. The magnetic field dependence of the enrichment of 73Ge can be explained by the relaxation mechanism.