129Xe-Xe molecular spin relaxation -: art. no. 113201
129Xe-Xe molecular spin relaxation -: art. no. 113201
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DOI：
10.1103/physrevlett.88.113201
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发表时间：
2002-03-18
影响因子：
8.6
通讯作者：
Walker, TG
中科院分区：
文献类型：
--
作者：
Chann, B;Nelson, IA;Walker, TG
我们确定了形成的绑定的129 -129-nitro分子作为主要的基本自旋弛豫过程中的密度低于14 amagat。作为气体成分的函数的低压Xe-Xe弛豫速率测量表明，Xe-Xe分子弛豫贡献1/T1 = 1/4.1 h的总观察到的弛豫速率。测得的速率是一致的理论估计推导出先前测得的NMR化学位移。在大气压下，分子弛豫比二元弛豫强一个数量级以上。分子和壁松弛机制的混淆在历史上导致壁松弛速率被高估。
We identify the formation of bound Xe-129-Xe molecules as the primary fundamental spin-relaxation process at densities below 14 amagat. Low pressure Xe relaxation rate measurements as a function of gas composition show that Xe-Xe molecular relaxation contributes 1/T1 = 1/4.1 h to the total observed relaxation rate. The measured rate is consistent with theoretical estimates deduced from previously measured NMR chemical shifts. At atmospheric pressure the molecular relaxation is more than an order of magnitude stronger than binary relaxation. Confusion of molecular and wall relaxation mechanisms has historically caused wall relaxation rates to be overestimated.