Efficient calculation of charge-transfer matrix elements for hole transfer in DNA

Area of Science:

• Computational chemistry
• Biophysics
• Molecular modeling

Background:

• Understanding charge transfer in DNA is crucial for biological processes and nanotechnology.
• Accurate computation of charge-transfer parameters is computationally demanding.
• Existing methods often struggle to incorporate environmental and dynamic effects realistically.

Purpose of the Study:

• To present a novel, efficient computational strategy for evaluating charge-transfer (CT) parameters in DNA.
• To enable accurate and cost-effective modeling of hole transfer dynamics in DNA.
• To provide a tool for studying DNA electronic properties under realistic conditions.

Main Methods:

• Utilized a fragment-orbital approach with SCC-DFTB for rapid electronic structure calculations.
• Integrated a quantum mechanics-molecular mechanics (QM/MM) scheme to capture environmental effects.
• Incorporated dynamical effects by performing calculations along classical molecular dynamics trajectories.

Main Results:

• The SCC-DFTB method demonstrated high accuracy in calculating site energies and coupling integrals compared to DFT and ab initio methods.
• The QM/MM coupling scheme effectively accounted for environmental influences on CT parameters.
• The integrated approach allows for a realistic simulation of charge-transfer processes in DNA.

Conclusions:

• The presented computational strategy offers a computationally efficient and accurate method for studying DNA charge transfer.
• This methodology facilitates a more realistic investigation of hole transfer mechanisms in DNA.
• The approach is valuable for advancing research in DNA electronics and related fields.