C-IBI: Targeting cumulative coordination within an iterative protocol to derive coarse-grained models of...

Area of Science:

• Computational chemistry
• Molecular modeling
• Physical chemistry

Background:

• Coarse-graining methods are essential for simulating large molecular systems.
• Traditional iterative Boltzmann inversion (IBI) can be computationally expensive and slow to converge.
• Accurate solvation thermodynamics are crucial for understanding chemical processes in solution.

Purpose of the Study:

• To introduce a novel coarse-graining strategy, coordination iterative Boltzmann inversion (C-IBI).
• To assess the ability of C-IBI to reproduce solvation thermodynamics of aqueous mixtures.
• To evaluate the convergence speed of C-IBI compared to IBI.

Main Methods:

• Developed a coarse-graining strategy using pair-wise cumulative coordination as a target function.
• Implemented a protocol similar to iterative Boltzmann inversion (IBI).
• Applied the coordination iterative Boltzmann inversion (C-IBI) method to binary and ternary aqueous mixtures.

Main Results:

• C-IBI successfully reproduces the solvation thermodynamics of binary and ternary aqueous mixtures.
• The method preserves pair-wise solution structure inherent in the underlying coarse-grained model.
• C-IBI demonstrated significantly faster convergence compared to the standard IBI method.
• Validated C-IBI's robustness by studying aqueous urea and triglycine solvation in aqueous urea.

Conclusions:

• Coordination iterative Boltzmann inversion (C-IBI) is an effective and efficient coarse-graining method for studying solvation thermodynamics.
• C-IBI offers a faster alternative to IBI for molecular simulations of aqueous mixtures.
• The method shows promise for complex systems, including solvation of small molecules and peptides in aqueous solutions.