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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
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On the structure of protonated methane
A J Heck1, L J de Koning, N M Nibbering
1Institite of Mass Spectrometry, University of Amsterdam, Nieuwe Achtergracht 129, 1018 WS, Amsterdam, The Netherlands.
Journal of the American Society for Mass Spectrometry
|November 19, 2013
Summary
Protonated methane reactivity with ammonia reveals distinct hydrogen behaviors. This study used Fourier transform-ion cyclotron resonance to explore chemical ionization gas effects on molecular structure.
Area of Science:
- Physical Chemistry
- Chemical Physics
- Isotope Chemistry
Background:
- Understanding ion-molecule reactions is crucial for chemical analysis.
- Protonated methane and its deuterated analogs are key species in ion chemistry.
- The role of chemical ionization gas in influencing reaction pathways requires further investigation.
Purpose of the Study:
- To investigate the reactivity of protonated perdeuteromethane and deuteronated methane with ammonia.
- To elucidate the mechanisms of proton and deuteron transfer in these systems.
- To explore the influence of chemical ionization gas on the structural dynamics of protonated methane.
Main Methods:
- Fourier transform-ion cyclotron resonance (FT-ICR) mass spectrometry.
- Chemical ionization (CI) ion source.
- Variable pressure studies.
Main Results:
- Proton and deuteron transfer reactions with ammonia showed chemically distinguishable hydrogens.
- The observed chemical behavior of protonated methane aligns with a theoretically predicted Cs symmetric structure.
- Fast interconversion of protonated methane structures was observed, influenced by the chemical ionization gas.
Conclusions:
- The study provides insights into the reactivity and structural dynamics of protonated methane and its isotopologues.
- Chemically distinct hydrogens in protonated methane were identified through reactions with ammonia.
- Chemical ionization gas plays a significant role in modulating the structural dynamics of ions.
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