Interaction-Deletion: A Composite Energy Method for the Optimization of Molecular Systems Selectively Removing...

Area of Science:

• Computational Chemistry
• Molecular Modeling
• Physical Chemistry

Background:

• Traditional electronic structure calculations struggle with complex molecular interactions.
• Quantifying the physical impact of individual pairwise interactions within molecules is difficult.

Purpose of the Study:

• To develop a composite energy method for analyzing molecular interactions.
• To quantify the effects of removing specific nonbonded interactions on molecular structure and energy.

Main Methods:

• A composite energy method using molecular fragments was developed.
• Selected nonbonded interactions were systematically removed to observe changes.
• Geometry optimizations were performed to analyze structural and energetic consequences.

Main Results:

• The method successfully quantified intramolecular hydrogen-bonding influences in hexanediol and cyclohexanediol.
• Applications to a Si(100) surface model and peptide systems (3₁₀-polyglycine, H⁺GPGG) demonstrated scalability.
• The cooperative nature of intramolecular hydrogen bonds was explored in 2-nitrobenzene-1,3-diol.

Conclusions:

• The composite energy method provides chemically meaningful insights into molecular interactions.
• It effectively quantifies concepts like preparation and reorganization energy.
• The hybrid scheme is versatile and applicable to diverse and complex molecular systems.