Considering the absence of significant radiative decay for either complex and similarity of energy barriers toward Pd(II)-C homolysis, we postulate the longer excited state lifetime of 1a may result from lower rates of unproductive NRD compared to 3 (i.e., NRD that does not result in Pd(II)-C homolysis). Longer excited state persistence would then account for higher quantum yield in the T-shaped complexes by extending the window of time in which thermal homolysis of the Pd(II)-C bond can occur. Please do not adjust margins Please do not adjust margins metal complexes was a surprising finding. These data thus demonstrate a latent one-electron reaction manifold is readily accessible in T-shaped organo-Pd(II) complexes -some of the most active organometallic species in modern Pd catalysisusing visible light as an external stimulus. The findings of this study may help to expand the synthetic toolbox of this central catalytic metal by shunting Pd away from its strong preference toward two-electron mechanisms.