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Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Quantum structure of the intermolecular proton bond
J R Roscioli1, L R McCunn, M A Johnson
1Sterling Chemistry Laboratory, Yale University, Post Office Box 208107, New Haven, CT 06520, USA.
Science (New York, N.Y.)
|April 14, 2007
Summary
Researchers studied shared proton interactions in isolated molecules using gas-phase ion spectroscopy. This technique revealed sharp spectral features, offering a detailed microscopic view of the intermolecular proton bond.
Area of Science:
- Chemical Physics
- Molecular Spectroscopy
- Biophysical Chemistry
Background:
- A proton shared between two molecules, [A.H+.B], is a common binding motif in biological systems.
- Studying these interactions via proton vibrations is challenging in condensed phases due to diffuse spectral features.
Purpose of the Study:
- To investigate the microscopic nature of the intermolecular proton bond in isolated [A.H+.B] ions.
- To overcome the limitations of condensed-phase studies by utilizing gas-phase ion spectroscopy.
Main Methods:
- Surveyed 18 cold, isolated [A.H+.B] ions.
- Employed advanced gas-phase ion spectroscopy techniques.
- Identified sharp spectral features associated with the shared proton and surrounding molecules.
Main Results:
- Successfully identified sharp spectral features for both the shared proton and the tethered molecules.
- Obtained a microscopic-level understanding of the intermolecular proton bond.
- Characterized the properties of the proton bond within a floppy polyatomic molecular context.
Conclusions:
- Gas-phase ion spectroscopy provides unprecedented detail on intermolecular proton bonds.
- This method allows for the analysis of proton bond properties at a microscopic scale.
- The findings facilitate a deeper understanding of ubiquitous soft binding motifs in biological processes.
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