The latter is caused by the increasing nuclear Larmor frequency. The ENDOR lines from different nuclei, which overlap at conventional X-band, become separated at high field. The pulse ENDOR study of short-lived paramagnetic intermediates, such as spin-correlated RPs and triplet states in the photosystems, is highly important for understanding the primary steps of photosynthesis.
In RPs, the unusual out-of-phase ESE signal appears which can be used for pulse www.selleckchem.com/products/jph203.html ENDOR detection. Although several ENDOR investigations of photosynthetic spin-correlated RPs have been reported, the lack of a simple theory of such systems complicates the interpretation of the results. Acknowledgments The authors thank the coworkers named in the references for their important contribution to this work. Financial support was obtained from the Max Planck Society ABT-888 cell line and the DFG (Sfb 663, TP A7), and from Russian Foundation for Basic Research (6-04-48021a). The President of Russian Federation grant for scientific schools (HШ-551.2008.3) is also acknowledged. References Biehl R, Plato M, Möbius K (1975) General TRIPLE resonance on free radicals in solution. Determination of relative signs of isotropic hyperfine coupling constants. J Chem Phys 63:3515–3522. doi:10.1063/1.431790 CrossRef Britt RD, Campbell KA, Peloquin JM, Gilchrist ML, Aznar CP, Dicus MM, Robblee J, Messinger J (2004) Recent pulsed EPR studies of the Photosystem
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