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Quantum Theory of DNA— An Approach to Electron Transfer in DNA. Introduction. motivation ⇔ Ikemura Conjecture Ikemura Conjecture “Electron transfer in DNA is playing an important role in the information exchanges among the various sections of DNA.”. H. Sugawara, 2005
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Quantum Theory of DNA—An Approach to Electron Transfer in DNA Introduction motivation ⇔ Ikemura Conjecture Ikemura Conjecture “Electron transfer in DNA is playing an important role in the information exchanges among the various sections of DNA.” H. Sugawara, 2005 Work being done with H. Ikemura Example
2. Field Theory Technique Standard technique in particle theory and in condensed matter theory but maybe not in quantum chemistry.Consider electrons interacting with the centers of potential (ions) located at Ri: electromagnetic interactions (gauge principle)
3. Hartree approximations Include in V(x) → Veff
Further approximations only nearest neighbors Then we have Special case of H → Su-Schrieffer-Heegger Hamiltonian b, g constant , j longitudinal →
can also be defined in a similar way Then we replace
Here was utilized
RNA transcription DNA replication
◎ Consider classical and longitudinal oscillation localized (tightly bound) wave function ◎ general case with classical oscillation
◎ The localization depends on the sign of and of ◎ Back to the descrete description applications Luminescence quenching Electric current Absorption of light
Luminescence quenching Ru-ligand luminescence mixed system absorption Rh provides electrons ⇒ quenching quenching occurs by a hole propagation inside DNA Note 1. Prokariote ・・・ closed string 2. Eukariote ・・・ open string end: telomere with certain protein
Probability of quenching DNA electrons transfer to (from) metals
Coupling to backbone electrons add This may be important in explaining the current?
(1) Efis within the band (2) Efis outside of the band semiconductor-like
Optical absorption (Sarukura’s proposal) excited band ground band em interaction
Conclusion Three dimensional string action for DNA is derived Approximate p-electron wave functions are derived Applications to luminescence quenching, electric current through DNA and optical absorption are formulated remaining problems Comparison with experiments Bound states with proteins Quantized phonon Improvement of approximations