Stable carbon isotope ratios of Fe3+/carboxylate mixture exposed to artificial sunlight were measured to gain kinetic isotope effects (KIEs).
Obtained KIEs were used to identify the vailed CC bond cleaving channel of oxalate.
Observed KIEs for the oxalate, malonate, and succinate mixtures were 5.9‰, 11.5‰, and 8.4‰, respectively.
Comparison of the observed KIEs with the proposed photolysis mechanism successfully identified the sequential dissociation of CC and Fe
O bonds as the C
C bond cleaving channel.