Nuclear quantum beats observed from photosynthetic charge separation
- Argonne National Lab., IL (United States); and others
In natural photosynthesis, efficient photoinduced charge-separation is achieved because of the unique structural and energetic relationships between the co-factors involved in this process. In turn, these unique properties give rise to unusual magnetic resonance responses when monitoring the charge-separation process with time-resolved electron paramagnetic resonance (epr). We have observed (at low temperatures) photo-induced low frequency oscillations in the transient epr responses from cyanobacterial Photosystem I (PSI) and pure photosynthetic bacteria. By comparing the signals from fully deuterated photosynthetic material having {sup 14}N or {sup 15}N we have identified these oscillations as nuclear quantum beats associated with the non-adiabatic change of the spin Hamiltonian at the instant of the laser pulse. The nuclear quantum beats can provide details of the electronic structures of the photo-oxidized primary electron donors in PSI and purple photosynthetic bacteria.
- Research Organization:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- DOE Contract Number:
- W-31109-ENG-38
- OSTI ID:
- 215142
- Report Number(s):
- CONF-950801-; TRN: 96:000922-0663
- Resource Relation:
- Conference: 210. national meeting of the American Chemical Society (ACS), Chicago, IL (United States), 20-25 Aug 1995; Other Information: PBD: 1995; Related Information: Is Part Of 210th ACS national meeting. Part 1 and 2; PB: 1866 p.
- Country of Publication:
- United States
- Language:
- English
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