A karplus-type relationship for deuterium quadrupole coupling constants. II. Inequivalent C2H sites in substituted acetic acids
Solid-state deuterium NMR spectra have been obtained for three substituted acetic acids. Analysis of the single-quantum and double-transition zero-field deuterium spectra shows that the methylene deuterons in a molecule, even though bound to the same carbon site, can have different values for the quadrupole coupling constant. The major source of the inequivalency has been traced to the neighboring oxygen atoms of the carboxylic acid group. A useful parameter for describing the geometry of the system is the 2HCalphaCacidHOH torsion angle. The value of the deuterium quadrupole coupling constant is correlated with the 2HCalphaCacidHOH torsion angle and is described by a Karplus-type relationship of the form A + B cos(θ) + C cos (2θ). © 1989.
Publication Source (Journal or Book title)
Journal of Magnetic Resonance (1969)
Jarrett, W., Guo, K., Jackisch, M., & Butler, L. (1989). A karplus-type relationship for deuterium quadrupole coupling constants. II. Inequivalent C2H sites in substituted acetic acids. Journal of Magnetic Resonance (1969), 82 (1), 76-85. https://doi.org/10.1016/0022-2364(89)90166-2