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Updated: Oct 28, 2025
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
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Structural and Energetic Properties of Haloacetonitrile - GeF4 Complexes
Anna W Waller1, Nicole M Weiss1, Daniel A Decato2
1Department of Chemistry, University of Wisconsin-Eau Claire Eau Claire, WI 54702.
Journal of Molecular Structure
|July 16, 2021
Summary
Halogen substitution in fluoroacetonitrile and chloroacetonitrile weakens germanium-nitrogen bonds in complexes with germanium tetrafluoride. This structural change impacts their behavior in condensed phases.
Area of Science:
- Inorganic Chemistry
- Computational Chemistry
- Solid-State Chemistry
Background:
- Germanium tetrafluoride (GeF4) forms complexes with nitriles.
- The electronic effects of substituents on these complexes are not fully understood.
- Understanding dative bond strength is crucial for predicting complex stability and reactivity.
Purpose of the Study:
- To investigate the structural and bonding properties of 1:1 and 2:1 complexes of FCH2CN and ClCH2CN with GeF4.
- To determine the impact of halogen substitution on the Ge-N dative bond.
- To compare gas-phase and solid-state structures of these complexes.
Main Methods:
- M06/aug-cc-pVTZ density functional theory calculations.
- Low-temperature, thin-film infrared (IR) spectroscopy.
- X-ray crystallography for the (FCH2CN)2-GeF4 complex.
Main Results:
- Halogen substitution significantly weakens Ge-N dative bonds, evidenced by longer Ge-N distances and reduced binding energies compared to CH3CN-GeF4.
- Halogenated complexes exhibit flatter Ge-N potential curves, indicating greater susceptibility to structural changes in condensed phases.
- Discrepancies between calculated gas-phase and experimental solid-state structures for 2:1 complexes suggest significant solid-state effects, including Ge-N bond compression.
Conclusions:
- Halogenated acetonitriles form weaker complexes with GeF4 than acetonitrile.
- The Ge-N bond strength and structural characteristics are sensitive to the chemical environment (gas vs. solid phase).
- These findings provide insights into the factors governing dative bond strength and structural dynamics in coordination complexes.
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