First a joke.
Quantum biology?
Moles tunnel into the classically forbidden region. But they make holes everywhere. They are delocalised!
[John Briggs asked if there was an entanglement measure of entropy per mole!].
Arrangement of electron carriers has a common structural motif in many proteins.
Optimisation principle. Change pigment and reduce quantum efficiency.
Electronic coupling between molecules is sensitive to orientation and relative direction of two molecules. Is it optimised?
There appears to be no functional role of the observed vibrational coherence associated with electron transfer.
Non-photochemical quenching (NPQ) in green plants. How does plant deal with excess photon flux? Triplet chlorophyl excitations can produce highly reactive singlet oxygen. Xanthophylll cycle induced by high light or change in pH.
"gear-shift" model as a mechanism for NPQ. Increase no. of conjugated bonds lowers excited state energy can act as an energy dump.
Quantum chemistry (DFT) calculations suggested that charge transfer is a potential quenching mechanism. Fleming group (Science 2005) tested this. Peak is at 1000 nm.
Artificial systems
Beyond vibrationally induced electron transfer in Gratzel cells and CdSe quantum dots coupled with methyl viogen. (Multi-excitons can be produced by a single photons).
Claims to see ballistic wave packet motion in CdSe nanocrystal and it is at 200 cm-1 which is LO phonon frequency.
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