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arXiv · 2107.10542

Low-Frequency Excitation of Singlet-Triplet Transitions. Application to Nuclear Hyperpolarization

Laurynas Dagys·Christian Bengs·Malcolm H. Levitt
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Abstract

Coupled pairs of nuclear spins-1/2 support one singlet state and three triplet states. Transitions between the singlet state and one of the triplet states may be driven by an oscillating low-frequency magnetic field, in the presence of couplings to a third nuclear spin, and a weak bias magnetic field.This phenomenon allows the generation of strong nuclear hyperpolarization of ${}^{13}\mathrm{C}$ nuclei, starting from the nuclear singlet polarization of a ${}^{1}\mathrm{H}$ spin pair, associated with the enriched para spin isomer of hydrogen gas. Hyperpolarization is demonstrated for two molecular system.

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Laurynas Dagys, Christian Bengs, Malcolm H. Levitt. 2021-07-22. Low-Frequency Excitation of Singlet-Triplet Transitions. Application to Nuclear Hyperpolarization. https://doi.org/10.1063/5.0065863

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