Predicting the halogen-n (n = 3-6) synthons to form the "windmill" pattern bonding based on the halogen-bonded...

Area of Science:

• Materials Science
• Computational Chemistry
• Solid-State Chemistry

Background:

• Halogen bonding is a significant non-covalent interaction.
• Cyclic halogen polymers present unique structural motifs.
• Understanding halogen bonding is crucial for materials design.

Purpose of the Study:

• Investigate the electronic properties and halogen-bonding capabilities of cyclic halogen polymers.
• Determine the factors influencing halogen bond strength in these systems.
• Explore potential applications in crystal engineering and self-assembly.

Main Methods:

• Density Functional Theory (DFT) calculations were employed.
• Analysis of electron density distribution and molecular geometry.
• Systematic study of (XBr)3 and (BrY)n (n=3-6) systems.

Main Results:

• Halogen atoms act as both electron donors and acceptors in halogen bonding.
• Halogen bond strength increases with atomic number (Cl < Br < I) in (XBr)3 trimers.
• Strongest Br-Br halogen bonds observed in (BrY)4 tetramers.
• Geometric parameters correlate with halogen bond strength.

Conclusions:

• The strength and geometry of halogen bonds are predictable using angular parameters.
• Iodine-containing synthons show potential for self-assembled crystal growth.
• DFT provides valuable insights into the behavior of cyclic halogen polymers.