原文由 janecy 发表:
我们组做稀土配位化合物的时候,有些配合物是不能用核磁表征的,据说是因为顺磁性的影响。不知哪位大虾能够详细解释一下是如何影响的?而且大部分稀土离子都是顺磁的,那些都不能做核磁吗?谢谢!
原文由 jwei1 发表:
Sorry I can't type Chinese now. Hope you understand.
Paramagnetic (顺磁性) atom does not have constant dipole moment. It aligns with applied external magnetic field. The electron spin dipole couples with magnetic spin dipole on neighboring atoms. In addition, the electron spin has fermi interaction with neighboring magnetic spin. Those nuclear spins relax so fast that it is hard or impossible to observe signals. Electron S = 5/2 is strong paramagnetic. You can try to increase temperature or do fast pulsing NMR.