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Updated: May 17, 2026
14:11
Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis
Published on: March 29, 2016
Nuclear magnetic shielding for hydrogen in selected isolated molecules.
Piotr Garbacz1, Karol Jackowski, Włodzimierz Makulski
1Faculty of Chemistry, University of Warsaw, Warszawa, Poland.
The Journal of Physical Chemistry. A
|November 3, 2012
Summary
This study provides precise experimental measurements of hydrogen molecule
Area of Science:
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Quantum Chemistry
- Physical Chemistry
Background:
- Accurate determination of magnetic shielding is crucial for validating computational chemistry methods.
- Previous experimental and computational data for hydrogen's magnetic shielding show slight discrepancies.
Purpose of the Study:
- To experimentally determine the absolute (1)H magnetic shielding for isolated hydrogen molecules and their deuterium isotopomers.
- To establish benchmark data for computational chemistry methods.
- To investigate isotope effects on magnetic shielding in molecular hydrogen.
Main Methods:
- Gas-phase Nuclear Magnetic Resonance (NMR) measurements using direct shielding measurements.
- Extrapolation of NMR frequencies to zero density.
- Analysis of density dependence of NMR frequencies for molecular hydrogen and atomic helium-3.
Main Results:
- The absolute isotropic magnetic shielding for molecular hydrogen (σ(0)(H(2))) was measured at 26.293(5) ppm at 300 K.
- Results align closely with prior experimental and computational values.
- Observed isotope effects in shielding for H(2), HD, and D(2) are consistent with theoretical predictions.
Conclusions:
- Precise experimental absolute shielding data for hydrogen molecules have been obtained.
- These findings will aid in developing and benchmarking computational methods for magnetic shielding calculations.
- The study confirms theoretical predictions regarding isotope effects in molecular hydrogen shielding.
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