超分子体系中次层相互作用对^(59)Co NMR谱的影响

The Second Sphere Interaction in the Supramolecular Complexes Studied by ^(59)Co Solid Static NMR

用59Co固体静态NMR对[Co（CN）6]3-离子与质子化的大环聚胺阳离子形成的超分子络合物的次层相互作用进行研究，结果表明，氢键的形成对该超分子结构的稳定性起了重要的作用．与仅有静电作用存在的K3[Co（CN）6]分子相比，59Co的三个化学位移张量的主值差值在超分子体系中明显增大．氢键作用的结果使[Co（CN）6]3-的对称性发生了改变，导致1T1g三重简并态发生分裂．分裂的大小反映了相互作用的程度．据此对该超分子体系的光水解量子产率的降低原因进行了重新解释．

59Co solid static NMR has demontrated that the hydrogen bonding interaction plays an important role in the supramolecular complexes formed by the [Co (CN)6]3- and protonated polyammonium macrocycles. The 59Co chemical shift spans Ω in the supramolecular complexes containing hydrogen boning interaction are considerably larger than that in K3[Co(CN)6] which bears the electronic static interaction only. Hydrogen bonding interaction changes the symmetry, of [Co(CN)6]3- in the supramolecules leading to the split of the triplex degenerate state 1T1g and the extent of the split reveals the extent of the hydrogen bonding. Accordingly, the changes of the aquation quantum yields in the supramolecules are alternatively rationalized.