Residual dipolar coupling

The residual dipolar coupling between two spins in a molecule occurs if the molecules in solution exhibit a partial alignment leading to an incomplete averaging of spatially anisotropic dipolar couplings.[1]

Partial molecular alignment leads to an incomplete averaging of anisotropic magnetic interactions such as the magnetic dipole-dipole interaction (also called dipolar coupling), the chemical shift anisotropy, or the electric quadrupole interaction. The resulting so-called residual anisotropic magnetic interactions are useful in biomolecular NMR spectroscopy.[2]

Liquid crystals are commonly used to permit the observation of residual dipolar couplings in high-resolution liquid-state NMR spectra.
  1. ^ F. Kramer, M.V. Deshmukh; S.J. Glaser (2004). "Residual dipolar coupling constants: An elementary derivation of key equations". Concepts in Magnetic Resonance. 21a (1): 10–21. doi:10.1002/cmr.a.20003.
  2. ^ Brunner, E. (2001). "Residual dipolar couplings in protein NMR". Concepts in Magnetic Resonance. 13 (4): 238–259. doi:10.1002/cmr.1012.