【摘要】 核自旋之间的各种各向异性相互作用都能用二阶张量表示,这些张量可分解成各向同性、对称以及反对称分量。本文针对化学位移各向异性相互作用,讨论了反对称分量的NMR性质,指出在MAS情形下,反对称分量对频移和谱宽的贡献仍是二阶小量。反对称分量与对称分量的非久期项对频移和谱宽的影响决定了MAS谱的极限分辨率。文中计算了MAS情形下这两种效应产生的粉末线型。更多还原

【Abstract】 The various anisotropic spin interactions which can be represented by the rank two tensors are decomposed into isotropic, symmetric, and antisymmetric constituents. This paper deals with the NMR properties of the antisymmetric constituent of chemical shift interaction. The antisymmetric constituent under MAS effects both the line position and the linewidth in second order. This contribution together with the effect from nonsecular terms of symmetric constituent determines the ultimate resolution of MAS spectra. The powder pattern caused by the above two effects under MAS is calculated.更多还原