Theoretical Prediction and Comprehensive Characterization of an All-Nitrogenatomic Ring, Cyclo[18]Nitrogen (N₁₈)

Area of Science:

• Theoretical Chemistry
• Materials Science
• Quantum Chemistry

Background:

• Cyclo[18]carbon, an 18-atom carbon ring, has been experimentally observed.
• Nitrogen allotropes are of significant interest due to their high energy content.

Purpose of the Study:

• To theoretically investigate the formation and properties of a novel macrocyclic nitrogen molecule, cyclo[18]nitrogen (N₁₈).
• To explore the stability, electronic structure, and decomposition mechanisms of N₁₈.

Main Methods:

• State-of-the-art quantum chemistry calculations.
• Comprehensive theoretical studies including geometric configurations, thermal decomposition, molecular dynamics, and spectral analysis.

Main Results:

• The formation of a macrocyclic system, cyclo[18]nitrogen (N₁₈), was predicted.
• N₁₈ exhibits a short lifetime at room temperature but is stable at very low temperatures.
• Detailed analysis of N₁₈'s electronic structure, including N-N bond nature, charge distribution, and aromaticity.

Conclusions:

• This study presents the first theoretical exploration of the macrocyclic N₁₈ molecule.
• It provides a systematic examination of a long-chain, isolated nitrogen substance, advancing the understanding of nitrogen allotropes.