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From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
06:44

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding

Published on: March 24, 2018

On the correlation between bond-length change and vibrational frequency shift in halogen-bonded complexes

Weizhou Wang1, Yu Zhang, Baoming Ji

  • 1College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022, China. wzwanglab@yahoo.com

The Journal of Chemical Physics
|June 21, 2011
PubMed

Insights

Density functional theory computations reveal a strong linear correlation between C-Hal bond length changes and vibrational frequency shifts in halogen bonds. This finding aids in understanding and predicting halogen bond interactions.

Area of Science:

  • Computational Chemistry
  • Chemical Physics
  • Spectroscopy

Background:

  • Halogen bonds (C-Hal···Y) are crucial non-covalent interactions.
  • Understanding these interactions requires analyzing bond length and vibrational frequency changes.

Purpose of the Study:

  • To investigate the relationship between C-Hal bond length changes and C-Hal stretch vibrational frequency shifts upon halogen bond formation.
  • To assess the reliability of this correlation using computational methods.

Main Methods:

  • Density functional theory (DFT) computations were employed.
  • Calculations focused on C-Hal bond length changes and vibrational frequency shifts in various halogen-bonded complexes.
  • Statistical analysis, including coefficient of determination, was used to evaluate the correlation.

Main Results:

  • A strong linear correlation was observed between C-Hal bond length changes and C-Hal stretch vibrational frequency shifts.
  • Coefficients of determination ranged from 0.94366 to 0.99219, indicating a very good correlation.
  • The correlation holds across different C-Hal bonds (Cl, Br, I) and electron donors (Y).

Conclusions:

  • The study confirms a robust linear relationship between geometric and spectroscopic parameters in halogen bonding.
  • This correlation provides a valuable tool for characterizing and predicting halogen bond strength and properties.
  • The findings are important for fields utilizing non-covalent interactions, such as supramolecular chemistry and drug design.

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