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Updated: Jun 23, 2025
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Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
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Coherent spin transport in a copper protein.
1Department of Technology, National Institute of Technology, Nara College, Yatacho 22, Yamato-koriyama, Nara, Japan. matsuura@chem.nara-k.ac.jp.
Journal of Molecular Modeling
|June 18, 2024
Summary
Spin polarization in copper proteins like azurin is significantly influenced by ligand groups, not the copper atom itself. This finding aids in understanding electron transport in single-molecule junctions.
Area of Science:
- Biophysics
- Quantum Chemistry
- Materials Science
Background:
- Azurin, a copper protein, exhibits fast electron transport and spin selectivity.
- Chiral-induced spin selectivity in peptide structures is a key area of research.
- Understanding spin polarization in biological molecules is crucial for molecular electronics.
Purpose of the Study:
- To calculate coherent electron/spin transport in azurin using the Landauer model.
- To investigate the factors influencing spin polarization in copper proteins.
- To correlate computational predictions with experimental techniques like scanning tunneling microscopy.
Main Methods:
- Landauer model combined with nonequilibrium Green's functions (NEGF) and density functional theory (DFT).
- Utilized QuantumATK software with the Perdew-Burke-Ernzerhof (PBE) functional for SGGA.
- Employed SIESTA package for valence atomic orbitals and norm-conserving pseudopotentials.
Main Results:
- Calculated large spin polarization in copper proteins, particularly azurin.
- Identified ligand group spin density as the primary driver of spin polarization.
- Demonstrated negligible contribution from the copper atom to spin polarization.
Conclusions:
- Spin polarization in copper proteins is predominantly enhanced by ligand groups.
- Computational findings support experimental studies on single-molecule junctions.
- The study provides insights into spin-selective electron transport in biological systems.
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