Nuclear Spin-Spin Coupling in HD, HT, and DT

Area of Science:

• Quantum Chemistry
• Nuclear Magnetic Resonance (NMR) Spectroscopy
• Beyond Standard Model Physics

Background:

• Nuclear spin-spin coupling constants (J) are sensitive probes of fundamental physics.
• Computational challenges limit the accuracy of theoretical J constant calculations.
• Existing theoretical J constants often show discrepancies with experimental values.

Purpose of the Study:

• To develop a computationally precise method for calculating the nuclear spin-spin coupling constant J.
• To resolve the discrepancy between theoretical and experimental J values in the hydrogen molecule.
• To improve the reliability of NMR theory for searching for new physics.

Main Methods:

• A variational approach was employed for calculating the J constant.
• Calculations were performed on the hydrogen molecule (H2) with controlled numerical precision.
• The adiabatic approximation was used, followed by an analysis of non-adiabatic effects.

Main Results:

• The J constant in H2 was calculated with controlled numerical precision.
• Discrepancies with experimental results were resolved by analyzing non-adiabatic effects.
• The analysis utilized experimental J values from HD, HT, and DT molecules.

Conclusions:

• The developed variational approach enhances the accuracy of J constant calculations.
• This improved theoretical framework increases the reliability of NMR for new physics searches.
• The study provides a more robust tool for exploring physics beyond the Standard Model through spin-spin coupling.