三自旋体系长寿命核自旋单重态的制备  

Preparation of Long-Lived Nuclear Singlet States in Three-Spin Systems

作　　者：郭海清 辛家祥 刘慧霞 魏达秀 姚叶锋 GUO Hai-qing;XIN Jia-xiang;LIU Hui-xia;WEI Da-xiu;YAO Ye-feng(Shanghai Key Laboratory of Magnetic Resonance,College of Physics and Materials Science,East China Normal University,Shanghai 200062,China)

机构地区：[1]华东师范大学物理与材料科学学院,上海市磁共振重点实验室,上海200062

出　　处：《波谱学杂志》2018年第3期345-352,共8页Chinese Journal of Magnetic Resonance

基　　金：上海市自然科学基金资助项目(16ZR1448300).

摘　　要：长寿命核自旋单重态的寿命(T_S)可以长于常规的纵向弛豫时间(T_1),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.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.

关 键 词：液体核磁共振 长寿命核自旋单重态 纵向弛豫时间 丙烯酸 

分 类 号：O482.53[理学—固体物理]