σ-Electrons Responsible for Cooperativity and Ring Equalization in Hydrogen-Bonded Supramolecular Polymers

Area of Science:

• Supramolecular Chemistry
• Theoretical Chemistry

Background:

• Hydrogen-bonded polymers, including urea, deltamide, and squaramide, exhibit unique cooperative properties.
• Understanding the electronic mechanisms behind these properties is crucial for materials science.

Purpose of the Study:

• To investigate the role of sigma-electron charge transfer in the cooperativity of hydrogen-bonded squaramide linear chains.
• To elucidate the relationship between electronic structure and cooperative phenomena in organic polymers.

Main Methods:

• Computational modeling of sigma-electronic systems.
• Analysis of charge transfer pathways in hydrogen-bonded polymer chains.

Main Results:

• A sigma-electron traveling through a hydrogen-bonded squaramide chain was visualized.
• Charge transfer within the sigma-electronic system was identified as the driving force for cooperativity.
• The findings apply to urea, deltamide, and squaramide polymers.

Conclusions:

• The study highlights the critical role of sigma-electron delocalization in achieving cooperativity in hydrogen-bonded organic polymers.
• This understanding provides a foundation for designing novel materials with tailored cooperative effects.