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Intrinsic Rashba coupling due to hydrogen bonding in DNA
S Varela1, B Montañes2, F López1
1School of Chemical Sciences and Engineering, Yachay Tech University, 100119 Urcuquí, Ecuador.
The Journal of Chemical Physics
|October 3, 2019
Summary
Hydrogen bonding significantly enhances spin-orbit coupling in DNA, a key factor in chiral-induced spin selectivity. This finding highlights the crucial role of hydrogen bonds, beyond just chirality, in biological systems.
Area of Science:
- Molecular Biophysics
- Quantum Chemistry
- Condensed Matter Physics
Background:
- Chirality plays a role in spin-selective effects in molecules.
- Hydrogen bonds are crucial in biological structures like DNA.
- Understanding spin-orbit coupling is vital for spintronics and molecular electronics.
Purpose of the Study:
- To develop an analytical model for hydrogen bonding's effect on spin-orbit coupling in DNA.
- To investigate the electric fields from hydrogen bond polarization in DNA base pairs.
- To derive the intrinsic Rashba coupling constant related to chiral-induced spin selectivity.
Main Methods:
- Analytical modeling of hydrogen bonding effects.
- Tight-binding analytical band folding approach.
- Analysis of electric fields due to hydrogen bond polarization.
Main Results:
- Derived an intrinsic Rashba coupling, ten times larger than previously estimated.
- Identified a predominant role for hydrogen bonding alongside chirality in biological molecules.
- The derived coupling dictates the order of spin-active effects in chiral-induced spin selectivity.
Conclusions:
- Hydrogen bonding significantly amplifies spin-orbit coupling in DNA.
- This effect is crucial for understanding chiral-induced spin selectivity in biological systems.
- Similar dominant effects are expected in hydrogen-bonded oligopeptides for electron transport.
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