The (29)Si spin-lattice relaxation in porous silica-based material 1, doped by ions Mn(2+) at a Si/Mn ratio of 3.5, is non-exponential, independent of magic-angle spinning (MAS) rates and governed by direct dipolar coupling between electron and nucleus where an electron relaxation time is estimated to be about 10(-8)s. In the absence of mutual energy-conserving spin flips (spin diffusion) in 1, the (29)Si T(2) time increases linearly with spinning rates. None was observed in diamagnetic porous system 2. The unexpected (29)Si T(2) dependence has been interpreted in terms of the large bulk magnetic susceptibility (BMS) effects. It has been shown that editing the (29)Si Hahn-echo MAS NMR spectra eliminates wide lines, belonging to (29)Si nuclei in the proximity of paramagnetic centers, and reduces the BMS broadenings in sideband patterns for nuclei remote from these centers.

中文翻译：

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在多孔顺磁性材料SiO（2）-MnO-Al（2）O（3）中的（29）Si T（1）和T（2）NMR弛豫。

（29）Si自旋晶格弛豫在多孔硅基材料1中，以Si / Mn比为3.5的离子Mn（2+）掺杂，是非指数的，独立于幻角旋转（MAS）速率和受电子与原子核之间直接偶极耦合的控制，其中电子弛豫时间估计约为10（-8）s。在没有互惠的自旋翻转（自旋扩散）的情况下，（29）Si T（2）时间随旋转速度线性增加。在抗磁性多孔系统2中未观察到任何现象。出乎意料的（29）Si T（2）依赖性已根据大体积磁化率（BMS）效应进行了解释。研究表明，编辑（29）Si Hahn-echo MAS NMR谱可消除宽线，该线属于顺磁中心附近的（29）Si核，