Molecular Structures and Motions in Solid Hexamethylethane by Proton Magnetic Resonance
Molecular Structures and Motions in Solid Hexamethylethane by Proton Magnetic Resonance
复制标题
通过质子磁共振研究固体六甲基乙烷中的分子结构和运动
DOI：
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发表时间：
1971
期刊：
影响因子：
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通讯作者：
George W. Smith
中科院分区：
文献类型：
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作者：
George W. Smith
固体六甲基乙烷的质子磁共振（PMR）研究揭示了低温相中叔丁基的C3′重取向（活化能约为3 kcal/mole）的存在。当温度升高到转变温度（152.5°K）以上时，一般分子重新取向突然发生。温度进一步升高会导致270°K以上的自扩散导致谱线逐渐变窄。自扩散的活化能为15.0 ± 0.3 kcal/mole。刚性晶格二阶矩（T < 80°K）与基于标准键长和键角的分子结构雅阁。
Proton magnetic resonance (PMR) studies of solid hexamethylethane reveal the existence of C3′ reorientation of the t‐butyl groups (activation energy ∼ 3 kcal/mole) in the low‐temperature phase. As the temperature is raised above the transition temperature (152.5°K) general molecular reorientation sets in abruptly. A further temperature increase leads to a gradual line narrowing due to self‐diffusion above 270°K. The activation energy for self‐diffusion is 15.0 ± 0.3 kcal/mole. The rigid lattice second moment (T < 80°K) is in accord with a molecular structure based on standard bond lengths and angles.