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Updated: May 23, 2026
06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
H-bonded clusters in the trimethylamine/water system: a matrix isolation and computational study
Mark Rozenberg1, Aharon Loewenschuss, Claus J Nielsen
1Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel.
The Journal of Physical Chemistry. A
|April 12, 2012
Summary
Researchers observed trimethylamine (TMA) and water molecule interactions using Matrix Isolation Fourier Transform Infrared Spectroscopy (MIS-FTIR). They identified a novel cluster formed by two TMA molecules and four water molecules, stabilized by hydrogen bonding.
Area of Science:
- Physical Chemistry
- Spectroscopy
- Environmental Science
Background:
- Trimethylamine (TMA) is an environmentally significant molecule.
- Understanding molecular interactions, particularly hydrogen bonding, is crucial in chemistry and environmental studies.
- Matrix Isolation Fourier Transform Infrared Spectroscopy (MIS-FTIR) is a powerful technique for studying unstable molecular complexes.
Purpose of the Study:
- To investigate the interaction products of trimethylamine (TMA) and water molecules.
- To characterize the structure and stability of these interaction products using spectroscopic methods.
- To elucidate the role of hydrogen bonding in the formation of molecular clusters.
Main Methods:
- Matrix Isolation Fourier Transform Infrared Spectroscopy (MIS-FTIR) was employed to trap and analyze TMA and water molecules in a solid argon matrix.
- Infrared spectra were analyzed for characteristic absorption bands in the O-H stretching region.
- Experimental results were compared with theoretical calculations (B3LYP/aug-cc-pVTZ) and empirical correlations for hydrogen-bonded complexes.
Main Results:
- New spectral bands were observed in the O-H stretching region, absent in spectra of pure TMA or water matrices.
- These bands, exhibiting red shifts, were assigned to a specific cluster structure: two TMA molecules flanking a closed ring of four hydrogen-bonded water molecules.
- The cluster formation was attributed to strong cooperative effects and significant stabilization energy (enthalpy), suggesting vapor-phase formation.
Conclusions:
- A novel molecular cluster involving trimethylamine and water has been identified and characterized.
- The study highlights the significant role of cooperative hydrogen bonding in stabilizing such clusters.
- The findings provide insights into the complex interactions of environmental molecules.
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