A quantitative measure for nuclear spin-spin, nuclear-electron (
hyperfine coupling) and electron-electron (fine
coupling in
EPR)
coupling in magnetic
resonance spectroscopy. The '
indirect' or scalar
NMR coupling constants are in a first approximation independent of the external magnetic field and are expressed in
.
Source:
PAC, 1994, 66, 1077
(Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994))
on page 1101
