长寿命核自旋单重态的寿命（TS）可以长于常规的纵向弛豫时间（T1），基于这个独特的优势，长寿命核自旋单重态具有较好的应用价值.本文对已有脉冲序列进行了改进，给出了适用于任意三自旋弱耦合体系长寿命核自旋单重态制备的参数计算方法，发现在同一个三自旋体系内核自旋单重态具有多种不同比例系数组合的形式，并以丙烯酸为例制备出了两种长寿命核自旋单重态，实验上观察到不同的核自旋单重态的寿命存在差异，另外我们还探究了温度对丙烯酸核自旋单重态寿命的影响.
郭海清
,
辛家祥
,
刘慧霞
,
魏达秀
,
姚叶锋
. 三自旋体系长寿命核自旋单重态的制备[J]. 波谱学杂志, 2018
, 35(3)
: 345
-352
.
DOI: 10.11938/cjmr20182619
Long-lived nuclear singlet states are widely used in NMR because they have longer lifetime (TS) than conventional longitudinal relaxation time (T1). In this paper, we present a new method to calculate the parameters for preparing long-lived nuclear singlet states, which is applicable to weakly-coupled three-spin systems. It was found that in the same three-spin system, there existed a variety of combination of singlet states with different proportional coefficients. Herein, we prepared two singlet states in an acrylic acid sample. The lifetime of the two states was measured experimentally, which showed significant difference. In addition, the effects of temperature on the singlet state lifetimes of acrylic acid were investigated.
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