Title:	Theoretical investigation of photosynthetic oxygen evolution
DNr:	SNIC 2018/3-518
Project Type:	SNIC Medium Compute
Principal Investigator:	Lars Kloo <lakloo@kth.se>
Affiliation:	Kungliga Tekniska högskolan
Duration:	2019-01-01 – 2020-01-01
Classification:	10499 10601 10407
Homepage:	https://www.kth.se/sv/che
Keywords:

Abstract

Photosynthetic oxygen evolution is one of the most fundamental processes in nature. However, the mechanism of O-O bond formation remains unclear. Theoretical and computational chemistry plays an important role in this mechanistic investigation. Very recently, structural intermediates S0,S1,S2,S3 of the oxygen-evolving complex (OEC) during have been detected by XFEL, which provides a reliable starting point to study O-O bond formation during the S3-S0 transition. To date, there have been several proposals in which oxo-oxyl coupling and nucleophilic attack mechanisms prevail. However, unprecedentedly, we propose a new S-state cycle where charge rearrangement of the OEC and Mn(VII)-involving O-O bond formation take place according to our experimental observation on Mn oxides. We would like to use DFT to investigate its feasibility and improve our proposed reaction scheme.