Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

π Electron Effects on Chemical Shift: Overview01:27

π Electron Effects on Chemical Shift: Overview

1.5K
An applied magnetic field causes loosely bound π-electrons in organic molecules to circulate, producing a local or induced diamagnetic field over a large spatial volume. As the molecules tumble in solution, the field generated by π-electrons in spherical substituents results in a zero net field. However, the net field generated by π-electrons in non-spherical substituents is not zero. The effect of this induced field depends on the orientation of the molecule with respect to B0,...
1.5K
π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds01:14

π Electron Effects on Chemical Shift: Aromatic and Antiaromatic Compounds

1.7K
In aromatic compounds, such as benzene, the circulation of (4n + 2) π-electrons sets up a diamagnetic or diatropic ring current around the perimeter of the molecule. This current induces a magnetic field that opposes the external field inside the ring and reinforces it on the outside. The protons in benzene are deshielded and exhibit high chemical shifts in the range 6.5–8.5 ppm. The shielding effect at the center of the ring is evident in complex aromatic molecules, such as...
1.7K
Spin–Spin Coupling Constant: Overview01:08

Spin–Spin Coupling Constant: Overview

1.2K
In bromoethane, the three methyl protons are coupled to the two methylene protons that are three bonds away. In accordance with the n+1 rule, the signal from the methyl protons is split into three peaks with 1:2:1 relative intensities. The methylene protons appear as a quartet, with the relative intensities of 1:3:3:1.
Qualitatively, any spin plus-half nucleus polarizes the spins of its electrons to the minus-half state. Consequently, the paired electron in the hydrogen–carbon bond must...
1.2K
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)01:20

Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)

1.5K
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
1.5K
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)01:22

Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)

1.3K
Vicinal or three-bond coupling is commonly observed between protons attached to adjacent carbons. Here, nuclear spin information is primarily transferred via electron spin interactions between adjacent C‑H bond orbitals. This generally favors the antiparallel arrangement of spins, so 3J values are usually positive.
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the...
1.3K
¹H NMR: Long-Range Coupling01:27

¹H NMR: Long-Range Coupling

2.4K
The coupling interactions of nuclei across four or more bonds are usually weak, with J values less than 1 Hz. While these are usually not observed in spectra, the presence of multiple bonds along the coupling pathway can result in observable long-range coupling.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene...
2.4K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

From Ultrafast Photoinduced Small Polarons to Cooperative and Macroscopic Charge-Transfer Phase Transition.

Angewandte Chemie (International ed. in English)·2024
Same author

Out-of-equilibrium dynamics driven by photoinduced charge transfer in CsCoFe Prussian blue analogue nanocrystals.

Faraday discussions·2022
Same author

Electron correlation driven non-adiabatic relaxation in molecules excited by an ultrashort extreme ultraviolet pulse.

Nature communications·2019
Same author

Control of H_{2} Dissociative Ionization in the Nonlinear Regime Using Vacuum Ultraviolet Free-Electron Laser Pulses.

Physical review letters·2018
Same author

Pattern formation in semiconductors.

Nature·2018
Same author

Sensitivity enhancement by multiple-contact cross-polarization under magic-angle spinning.

Journal of magnetic resonance (San Diego, Calif. : 1997)·2017
Same journal

Experimental and computational <sup>11</sup>B NMR comparative study of MOVPE-grown rhombohedral and bulk hexagonal boron nitride.

Solid state nuclear magnetic resonance·2026
Same journal

Determination of <sup>137</sup>Ba nuclear quadrupole interactions in solids: a comparison of high field and zero field approaches.

Solid state nuclear magnetic resonance·2026
Same journal

Probing interlayer bromide in solvent intercalation of layered yttrium hydroxide via <sup>79/81</sup>Br SSNMR spectroscopy.

Solid state nuclear magnetic resonance·2026
Same journal

Single crystal sapphire spacers for in situ angle sensing and rotor stability diagnostics in MAS NMR.

Solid state nuclear magnetic resonance·2026
Same journal

Insights into the local adsorption of CO<sub>2</sub> in UiO-66.

Solid state nuclear magnetic resonance·2026
Same journal

<sup>75</sup>As NQR characterisation of cobaltite (CoAsS).

Solid state nuclear magnetic resonance·2026
See all related articles

Related Experiment Video

Updated: Apr 27, 2026

Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR
10:54

Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR

Published on: February 23, 2016

10.3K

Cross-polarization dynamics and spin diffusion in some aromatic compounds

J Hirschinger1, M Hervé

  • 1Institut de Chimie, UMR 50 CNRS, Université Louis Pasteur, Strasbourg, France.

Solid State Nuclear Magnetic Resonance
|June 1, 1994
PubMed
Summary
This summary is machine-generated.

Inversion-recovery cross-polarization (IRCP) experiments reveal that proton spin diffusion governs the dynamics of aromatic carbons in indole derivatives. A relaxation model accurately describes this spin diffusion process for DMI and related compounds.

More Related Videos

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
11:44

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Published on: November 12, 2016

19.6K
Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
09:00

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser

Published on: June 28, 2018

9.3K

Related Experiment Videos

Last Updated: Apr 27, 2026

Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR
10:54

Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR

Published on: February 23, 2016

10.3K
Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
11:44

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Published on: November 12, 2016

19.6K
Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
09:00

Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser

Published on: June 28, 2018

9.3K

Area of Science:

  • Solid-state Nuclear Magnetic Resonance (NMR) Spectroscopy
  • Materials Science
  • Organic Chemistry

Background:

  • Protonated aromatic carbons in organic molecules exhibit complex cross-polarization dynamics.
  • Understanding these dynamics is crucial for characterizing molecular structures and interactions.

Purpose of the Study:

  • To investigate the 13C-1H cross-polarization dynamics of protonated aromatic carbons.
  • To elucidate the role of proton spin diffusion in these dynamics.
  • To develop and validate a model for describing the observed phenomena.

Main Methods:

  • Application of inversion-recovery cross-polarization (IRCP) magic-angle spinning experiments.
  • Utilizing 13C-detected proton spin diffusion (SD) experiments.
  • Analysis of experimental data using a phenomenological spin diffusion model.

Main Results:

  • The slow-decaying stage of IRCP experiments is controlled by proton spin diffusion.
  • A phenomenological model treating spin diffusion as relaxation shows excellent agreement with IRCP and SD data for DMI and derivatives.
  • Spin diffusion time constants correlate with local dipolar interaction networks.
  • The model is inadequate for ferrocene due to inhomogeneous intramolecular spin diffusion.

Conclusions:

  • Proton spin diffusion is a key factor in 13C-1H cross-polarization dynamics for aromatic systems.
  • The developed relaxation model effectively describes spin diffusion in DMI and its derivatives.
  • Ferrocene presents unique characteristics in its intramolecular spin diffusion behavior.