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Updated: Sep 24, 2025
06:35
Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
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Non-scrambling of hydrogen in NH4 +(H2O)3 clusters
K Hansen1,2, A E K Sundén3, K Støchkel4
1Center for Joint Quantum Studies, Department of Physics, Tianjin University Tianjin 300072 China KlavsHansen@tju.edu.cn.
RSC Advances
|May 6, 2022
Summary
Protonated ammonia-doped deuterated water clusters show a strong odd-even effect in their decay. Evaporation rates reveal distinct behavior for light, heavy, and mixed water molecules, indicating limited hydrogen scrambling.
Area of Science:
- Physical Chemistry
- Chemical Physics
- Spectroscopy
Background:
- Investigating the properties of water clusters is crucial for understanding hydrogen bonding and solvation.
- Ammonia-doped water clusters offer a model system to study proton transfer and dissociation dynamics.
- Deuteration provides a means to probe isotopic effects in molecular interactions and reaction pathways.
Purpose of the Study:
- To measure the metastable decay of protonated, ammonia-doped, deuterated water clusters.
- To analyze the influence of deuterium incorporation on cluster stability and dissociation.
- To investigate the degree of hydrogen scrambling between ammonia and water molecules during decay.
Main Methods:
- Production of protonated, ammonia-doped, deuterated water clusters (dn-NH4+(H2O)3, n=0-6) using an electrospray source.
- Mass spectrometry to detect and quantify cluster fragments and their decay products.
- Analysis of metastable decay patterns to determine dissociation pathways and kinetics.
Main Results:
- A very strong odd-even effect was observed in the mass spectra, suggesting limited hydrogen scrambling.
- The relative evaporation rate constant for light water (H2O) was nearly double that of heavy water (D2O).
- Mixed isotopologues exhibited intermediate evaporation rates, consistent with partial isotopic mixing.
Conclusions:
- The observed odd-even effect points to a low degree of hydrogen scrambling between ammonia and water moieties.
- Isotopic differences in evaporation rates highlight the significant impact of deuterium substitution on water cluster stability.
- These findings provide insights into the fundamental processes governing protonated water cluster decay and solvation.
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