Recent progress in atomistic modeling of light-harvesting complexes: a mini review

Area of Science:

• Computational Chemistry
• Biophysics
• Quantum Mechanics

Background:

• Biological light-harvesting (LH) complexes are crucial for photosynthesis.
• Their large size and complex electronic structures necessitate advanced computational methods.
• Understanding exciton dynamics requires accurate calculation of excitation energies and couplings.

Purpose of the Study:

• To review recent advances in atomistic modeling of LH complexes.
• To present a superior multiscale computational approach for analyzing LH systems.
• To provide a theoretical foundation for the enhanced multiscale protocol.

Main Methods:

• Utilizing a multiscale approach combining density functional tight-binding (DFTB) with excited state calculations.
• Implementing an enhanced protocol that improves the description of internal vibrational dynamics.
• Comparing results with classical molecular dynamics simulations and experimental data.

Main Results:

• The enhanced multiscale approach provides a more accurate description of pigment molecule dynamics.
• Calculated spectral densities show good agreement with experimental data for bacterial and plant LH systems.
• The DFTB-based method is superior to classical molecular dynamics for these properties.

Conclusions:

• The developed multiscale protocol offers a powerful tool for studying LH complexes.
• This method accurately predicts spectral densities, crucial for understanding exciton dynamics.
• Advances in atomistic modeling are key to elucidating photosynthetic energy transfer mechanisms.