On the electron tunneling in molecules: a generalized orthogonalization procedure for finding tunneling orbitals

Area of Science:

• Quantum Chemistry
• Biophysics
• Computational Chemistry

Background:

• Long-distance electron transfer is crucial in biological and chemical systems.
• Accurately identifying tunneling orbitals is key to understanding electron transfer dynamics.
• Current methods for calculating tunneling orbitals are often computationally intensive.

Purpose of the Study:

• To develop a simplified and computationally efficient method for determining tunneling orbitals in long-distance electron transfer systems.
• To reduce the computational cost associated with traditional biorthogonalization techniques.

Main Methods:

• The study proposes an approximate biorthogonalization of many-electron donor and acceptor states.
• The simplified procedure requires only a portion of the system (donor or acceptor complex plus part of the bridge).
• This method is practically equivalent to full biorthogonalization but significantly less demanding computationally.

Main Results:

• A computationally simpler method for identifying tunneling orbitals has been established.
• The simplified approach yields results comparable to more complex, traditional methods.
• Successful application to models of biological electron transfer, including Ru-modified azurin and cytochrome c oxidase.

Conclusions:

• The proposed method offers a practical and efficient way to study electron tunneling.
• This simplification can accelerate research in areas like biological electron transfer and molecular electronics.
• The technique provides valuable insights into the mechanism of long-distance electron transfer.