Classification of So-Called Non-Covalent Interactions Based on VSEPR Model.

Area of Science:

• Chemistry
• Chemical Physics
• Computational Chemistry

Background:

• Numerous chemical interactions, like hydrogen bonds, are crucial in biological and chemical processes.
• Existing classifications (e.g., σ-hole, π-hole bonds) face challenges due to overlapping characteristics and naming inconsistencies.
• Element properties, such as hydrogen's dual role as Lewis acid or base, further complicate interaction classification.

Purpose of the Study:

• To address the disadvantages and chaos in current classifications and naming conventions for chemical interactions.
• To propose a unified and simpler classification system for various intermolecular forces.
• To highlight the underlying mechanisms governing these interactions.

Main Methods:

• Analysis of existing literature on chemical interactions and their classifications.
• Examination of the role of σ-holes and π-holes in non-covalent interactions.
• Application of the valence-shell electron-pair repulsion (VSEPR) model for a new classification framework.

Main Results:

• The majority of chemical interactions share common mechanisms involving electron charge shifts.
• Interactions cause specific geometric changes in interacting species, predictable by VSEPR theory.
• A new, simple classification system based on VSEPR is proposed.

Conclusions:

• Current interaction classifications are complex and often inconsistent.
• A VSEPR-based classification offers a more unified approach to understanding chemical interactions.
• The proposed classification is open to incorporating additional interactions and processes.