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Analysis of Complex Molecules and Their Reactions on Surfaces by Means of Cluster-Induced Desorption/Ionization Mass Spectrometry
Published on: March 1, 2020
DFT study of the ExBox·aromatic hydrocarbon host-guest complex.
1Department of Chemistry, Trinity University, San Antonio, Texas 78212, USA. sbachrach@trinity.edu
The Journal of Physical Chemistry. A
|August 10, 2013
Summary
ExBox(4+) forms host-guest complexes with linear acenes. Binding energy increases with acene size, showing favorable interactions in gas and solution phases for these supramolecular structures.
Area of Science:
- Supramolecular Chemistry
- Computational Chemistry
- Organic Chemistry
Background:
- ExBox(4+) is a macrocyclic host molecule.
- Linear acenes are polycyclic aromatic hydrocarbons with potential host-guest applications.
- Understanding host-guest complexation is crucial for designing new materials.
Purpose of the Study:
- To investigate the structural and energetic properties of ExBox(4+) host-guest complexes.
- To explore the influence of acene size on complex stability.
- To validate computational models against experimental data.
Main Methods:
- Density Functional Theory (DFT) calculations using the ωB97X-D/6-311G(d,p) level of theory.
- Optimization of ExBox(4+) and its complexes in both gas and solution phases.
- Comparison of calculated structures with available X-ray crystallographic data.
Main Results:
- The structure of ExBox(4+) undergoes conformational changes from gas to solid phase.
- Calculated complex structures for anthracene and tetracene show excellent agreement with X-ray data.
- Gas phase binding energies correlate linearly with acene size.
- All complexes are predicted to have exergonic binding free energies in both phases.
Conclusions:
- ExBox(4+) effectively binds linear acenes, with binding strength increasing with acene size.
- DFT calculations provide accurate predictions for these host-guest systems.
- The findings support the potential of ExBox(4+) for applications involving linear acene recognition.
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