Low-frequency excitation of singlet-triplet transitions. Application to nuclear hyperpolarization
Low-frequency excitation of singlet-triplet transitions. Application to nuclear hyperpolarization
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DOI：
10.1063/5.0065863
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发表时间：
2021-10-21
影响因子：
4.4
通讯作者：
Levitt, Malcolm H.
中科院分区：
文献类型：
--
作者：
Dagys, Laurynas;Bengs, Christian;Levitt, Malcolm H.
自旋为1/2的耦合对支持一个单重态和三个三重态。在存在与第三核自旋的耦合和弱偏置磁场的情况下，单重态和三重态之一之间的跃迁可以由振荡的低频磁场驱动。振荡场与偏置场方向相同，称为WOLF（弱振荡低场）脉冲。WOLF脉冲的应用允许产生强的核超极化的C-13核，从核单线态极化的H-1自旋对，与丰富的氢气的对位自旋异构体。超极化证明了两个分子系统。(c)2021年作者。所有文章内容，除非另有说明，是根据知识共享署名（CC BY）许可证（http：//creativecommons.org/licenses/by/4.0/）。
Coupled pairs of nuclear spin-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. The oscillating field is in the same direction as the bias field and is called a WOLF (Weak Oscillating Low Field) pulse. Application of a WOLF pulse allows for the generation of strong nuclear hyperpolarization of C-13 nuclei, starting from the nuclear singlet polarization of a H-1 spin pair, associated with the enriched para-spin isomer of hydrogen gas. Hyperpolarization is demonstrated for two molecular systems. (c) 2021 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license(http://creativecommons.org/licenses/by/4.0/).