37 research outputs found
The solid-state photo-CIDNP effect
The solid-state photo-CIDNP effect is the occurrence of a non-Boltzmann nuclear spin polarization in rigid samples upon illumination. For solid-state NMR, which can detect this enhanced nuclear polarization as a strong modification of signal intensity, the effect allows for new classes of experiments. Currently, the photo- and spin-chemical machinery of various RCs is studied by photo-CIDNP MAS NMR in detail. Until now, the effect has only been observed at high magnetic fields with 13C and 15N MAS NMR and in natural photosynthetic RC preparations in which blocking of the acceptor leads to cyclic electron transfer. In terms of irreversible thermodynamics, the high-order spin structure of the initial radical pair can be considered as a transient order phenomenon emerging under non-equilibrium conditions and as a first manifestation of order in the photosynthetic process. The solid-state photo-CIDNP effect appears to be an intrinsic property of natural RCs. The conditions of its occurrence seem to be conserved in evolution. The effect may be based on the same fundamental principles as the highly optimized electron transfer. Hence, the effect may allow for guiding artificial photosynthesis
Photochemically Induced Nuclear Spin Polarization in Bacterial Photosynthetic Reaction Centers: Assignments of the 15
Natural abundance solid-state carbon NMR studies of photosynthetic reaction centers with photoinduced polarization.
Photochemically induced dynamic nuclear polarization in bacterial photosynthetic reaction centres observed by 13C solid-state NMR
Comment on “Quantum trajectory tests of radical-pair quantum dynamics in CIDNP measurements of photosynthetic reaction centers” [Chem. Phys. Lett. 640 (2015) 40–45]
13C Photo-CIDNP MAS NMR Studies on Oriented Reaction Centers
Solid state NMR/Biophysical Organic Chemistr