Dual Singlet Excited-State Quenching Mechanisms in an Artificial Caroteno-Phthalocyanine Light Harvesting Antenna.

ABSTRACT: Under excess illumination, photosystem II of plants dissipates excess energy through the quenching of chlorophyll fluorescence in the light harvesting antenna. Various models involving chlorophyll quenching by carotenoids have been proposed, including (i) direct energy transfer from chlorophyll to the low-lying optically forbidden carotenoid S₁ state, (ii) formation of a collective quenched chlorophyll-carotenoid S₁ excitonic state, (iii) chlorophyll-carotenoid charge separation and recombination, and (iv) chlorophyll-chlorophyll charge separation and recombination. In previous work, the first three processes were mimicked in model systems: in a Zn-phthalocyanine-carotenoid dyad with an amide linker, direct energy transfer was observed by femtosecond transient absorpt

SUBMITTER: Ravensbergen J 

PROVIDER: S-EPMC8796278 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature