The Largest ~(15)N-~(15)N Coupling Constant Across an NHN Hydrogen Bond

摘要

Since the discovery of NMR coupling constants across hydrogen bonds A-H…B containing nuclei with spin 1/2,such as A,B=~(19)F,~(15)N,it has been established that these NMR parameters can not only be used to detect hydrogen bridges in biomolecules but also to determine the geometries of strong hydrogen bonds in solution.It has been shown experimentally and by ab initio calculations that scalar two-bond coupling constants ~2J_(AB)attain maximum values when the A-B distances are at a minimum.