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Updated: Jun 10, 2026
10:40
High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Rovibrational levels of HD.
Krzysztof Pachucki1, Jacek Komasa
1Institute of Theoretical Physics, University of Warsaw, Hoza 69, 00-681 Warsaw, Poland. krp@fuw.edu.pl
Physical Chemistry Chemical Physics : PCCP
|August 6, 2010
Summary
High-accuracy calculations for the molecular hydrogen deuteride (HD) dissociation energy were performed. Theoretical results show a slight discrepancy with the most precise experimental measurements, advancing molecular physics understanding.
Area of Science:
- Quantum Chemistry
- Molecular Spectroscopy
- Atomic Physics
Background:
- The molecular hydrogen deuteride (HD) is a fundamental system for testing quantum mechanical theories.
- Precise calculation of its dissociation energy provides critical benchmarks for theoretical models.
Purpose of the Study:
- To compute highly accurate dissociation energies for all rotation-vibrational states of HD.
- To investigate the impact of nonadiabatic, relativistic, and quantum electrodynamic effects on the dissociation energy.
Main Methods:
- Inclusion of nonadiabatic, relativistic (alpha^2), and quantum electrodynamic (alpha^3) effects in calculations.
- Approximate treatment of higher-order alpha^4 corrections and finite nuclear size effects.
Main Results:
- The dissociation energy for the ground molecular state of HD was calculated to be 36 405.7828(10) cm(-1).
- A small disagreement was observed between the calculated value and the most precise experimental data.
Conclusions:
- The theoretical calculations provide a highly accurate prediction for the HD dissociation energy.
- The observed discrepancy suggests areas for refinement in both theoretical models and experimental measurements.
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