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Accessing long-lived disconnected spin-1/2 eigenstates through spins > 1/2
Kevin Claytor1, Thomas Theis, Yesu Feng
1Department of Physics, ‡Department of Chemistry, §Duke Small Molecule Synthesis Facility, ∥Department of Radiology, and ⊥Department of Biomedical Engineering, Duke University , Durham, North Carolina 27708, United States.
Journal of the American Chemical Society
|September 18, 2014
Summary
Chemically equivalent spin-1/2 nuclei can form long-lived states. Coupling with deuterium (a spin > 1/2 nucleus) enables population transfer into these states, offering potential for polarization storage.
Area of Science:
- Nuclear Magnetic Resonance (NMR) Spectroscopy
- Quantum Information Science
- Physical Chemistry
Background:
- Pairs of chemically equivalent spin-1/2 nuclei can form long-lived quantum states.
- These states exhibit significantly longer lifetimes than conventional magnetization.
- Quadrupolar interactions from nuclei with spin > 1/2 typically induce rapid relaxation.
Purpose of the Study:
- To extend the known classes of molecules with accessible long-lived states.
- To investigate the role of deuterium (spin > 1/2) in accessing long-lived states in systems with spin-1/2 pairs.
- To explore the potential of these states for polarization storage.
Main Methods:
- Theoretical analysis of spin dynamics.
- Nuclear Magnetic Resonance (NMR) experiments.
- Investigating scalar couplings between deuterium and carbon-13 nuclei.
Main Results:
- Demonstrated that deuterium coupling can facilitate population transfer into long-lived states.
- Showed that these long-lived states are resistant to dominant relaxation mechanisms.
- Confirmed that simple deuteration of molecules with natural abundance carbon-13 pairs is sufficient for lifetime measurements.
Conclusions:
- Molecules with carbon-13 pairs directly bound to deuterium are promising candidates for polarization storage.
- Scalar couplings can overcome the fast relaxation typically induced by quadrupolar nuclei.
- This research opens new avenues for utilizing long-lived states in NMR.
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