DMRG/FQ: A Polarizable Embedding Approach Combining Density Matrix Renormalization Group and Fluctuating Charges

Area of Science:

• Computational Chemistry
• Quantum Mechanics
• Molecular Dynamics

Background:

• Simulating electronic excited states in solution is challenging due to complex solute-solvent interactions.
• Accurate modeling requires capturing both strong electronic correlation and solvent polarization effects.

Purpose of the Study:

• To develop an integrated multiscale framework for simulating electronic excited states in solution.
• To combine the strengths of Density Matrix Renormalization Group (DMRG) and polarizable fluctuating-charge (FQ) models.

Main Methods:

• Developed a multiscale framework integrating DMRG with a polarizable FQ force field.
• Employed QM/MM embedding with DMRG for electronic structure and FQ for solvent polarization.
• Utilized extensive molecular dynamics sampling for solvated systems.

Main Results:

• Achieved reliable calculations of excitation energies and solvatochromic shifts.
• Demonstrated close agreement between computational results and experimental data.
• Highlighted the crucial role of mutual solute-solvent polarization.

Conclusions:

• The DMRG/FQ approach accurately captures electronic excited states in solution.
• This method is vital for understanding solute-solvent interactions, especially those involving hydrogen bonding.
• The framework provides a robust tool for theoretical chemistry research.