ESR study on the interaction between a positively charged spin probe and the silica gel surface
ESR study on the interaction between a positively charged spin probe and the silica gel surface
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带正电自旋探针与硅胶表面相互作用的 ESR 研究
DOI：
10.1016/0021-9797(83)90040-1
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
G. Martini
中科院分区：
文献类型：
--
作者：
M. Romanelli;M. Ottaviani;G. Martini
利用带正电荷的4-三甲铵-2，2，6，6-四甲基哌啶-1-氧氮氧自由基的电子自旋共振（ESR）谱线研究了水在窄孔硅胶（直径4 nm）上吸附的结构性质.从孔内不同区域中的自由基获得不同的光谱，作为与表面的距离的函数。自由基表现出慢动作的条件下，在第一水层附近的表面（主要的相互作用区域），而快速运动的条件下，在二次相互作用区域。通过计算机模拟计算了自由基在慢运动和快运动条件下的分配常数和自由基运动的关联时间。并与其它自旋探针在类似系统中的结果进行了比较。
The electron spin resonance lineshape of the positively charged 4-trimethylammonium-2,2,6,6-tetramethylpiperidine-1-oxyl nitroxide radical has been used for an investigation of the structural properties of water adsorbed on narrow-pore (4 nm diameter) silica gel. Different spectra were obtained from the radical in the different regions inside the pores, as a function of the distance from the surface. The radical showed slow-motion conditions in the first water layers near the surface (primary interaction region), while fast-motion conditions applied in the secondary interaction region. The partition constant of the radical between the two regions and the correlation times for the radical's motion have been calculated through a computer simulation in slow- and fast-motion conditions. The results have been compared with those obtained with other spin probes in similar systems.