How Nature Makes O₂: an Electronic Level Mechanism for Water Oxidation in Photosynthesis.

ABSTRACT: In this paper, we combine broken symmetry density functional calculations and electron paramagnetic resonance analysis to obtain the electronic structure of the penultimate S₃ state of nature's water-oxidizing complex and determine the electronic pathway of O-O bond formation. Analysis of the electronic structure changes along the reaction path shows that two spin crossovers, facilitated by the geometry and magnetism of the water-oxidizing complex, are used to provide a unique low-energy pathway. The pathway is facilitated via the formation and stabilization of the [O₂]^3- ion. This ion is formed between ligated deprotonated substrate waters, O5 and O6, and is stabilized by antiferromagnetic interaction with the Mn ions of the complex. Combining the computat

SUBMITTER: Rummel F 

PROVIDER: S-EPMC9589598 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature