Related Experiment Video
Updated: Jun 24, 2026

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Hydrogen bonding in 1,2-diazine-chloranilic acid (2 : 1) studied by a 14N nuclear quadrupole coupling tensor and
Janez Seliger1, Veselko Zagar, Kazuma Gotoh
1Jozef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia.
Abstract:
Protons involved in the H-bond system in 1,2-diazine-chloranilic acid (2 : 1) are assumed to be in jumping motion in the double-minimum potential corresponding to the two extreme electronic states of O-H...N and O-...H-N+. 14N nuclear quadrupole coupling constants were determined by 1H-14N nuclear quadrupole double resonance. Assuming that the observed coupling constants are result of a fast exchange of the two extreme electronic states, the coupling constants for each state were estimated by use of the equilibrium populations of the two extreme states determined from multi-temperature X-ray single-crystal diffraction. It was suggested that not only the population but also the electron distribution of the extreme electronic states itself changes with temperature.
More Related Videos
10:52Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
09:37Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Related Concept Videos
2D NMR: Overview of Heteronuclear Correlation Techniques
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
¹H NMR: Complex Splitting
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied first.
¹³C NMR: ¹H–¹³C Decoupling
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...