School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK.
Philos Trans A Math Phys Eng Sci. 2013 Aug 5;371(1998):20120102. doi: 10.1098/rsta.2012.0102. Print 2013 Sep 13.
We report a solid-state NMR study of the anisotropic nuclear spin interactions in H₂O@C₆₀ at room temperature. We find evidence of significant dipole-dipole interactions between the water protons, and also a proton chemical shift anisotropy (CSA) interaction. The principal axes of these interaction tensors are found to be perpendicular. The magnitude of the CSA is too large to be explained by a model in which the water molecules are partially aligned with respect to an external axis. The evidence indicates that the observed CSA is caused by a distortion of the geometry or electronic structure of the fullerene cages, in response to the presence of the endohedral water.
我们报告了在室温下对 H₂O@C₆₀ 中各向异性核自旋相互作用的固态 NMR 研究。我们发现水质子之间存在显著的偶极-偶极相互作用，还有质子化学位移各向异性（CSA）相互作用。这些相互作用张量的主轴被发现是相互垂直的。CSA 的大小太大，不能用一个模型来解释，在这个模型中，水分子相对于一个外部轴部分对齐。这一证据表明，所观察到的 CSA 是由富勒烯笼的几何形状或电子结构的变形引起的，这是对内笼水的存在的响应。
