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

Spin–Spin Coupling Constant: Overview01:08

Spin–Spin Coupling Constant: Overview

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 have a...
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)01:22

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

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 involved orbitals. The...
NMR Spectroscopy: Spin–Spin Coupling01:08

NMR Spectroscopy: Spin–Spin Coupling

The spin state of an NMR-active nucleus can have a slight effect on its immediate electronic environment. This effect propagates through the intervening bonds and affects the electronic environments of NMR-active nuclei up to three bonds away; occasionally, even farther. This phenomenon is called spin–spin coupling or J-coupling. Coupling interactions are mutual and result in small changes in the absorption frequencies of both nuclei involved. While nuclei of the same element are involved in...
Spin–Spin Coupling: One-Bond Coupling01:17

Spin–Spin Coupling: One-Bond Coupling

Coupling interactions are strongest between NMR-active nuclei bonded to each other, where spin information can be transmitted directly through the pair of bonding electrons. While nuclei polarize their electrons to the opposite spins, the bonding electron pair has opposite spins. Configurations with antiparallel nuclear spins are expected to be lower in energy. When coupling makes antiparallel states more favorable, J is considered to have a positive value. The one-bond coupling constant, 1J,...
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)01:20

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

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...
Atomic Nuclei: Nuclear Spin State Overview01:03

Atomic Nuclei: Nuclear Spin State Overview

NMR-active nuclei have energy levels called 'spin states' that are associated with the orientations of their nuclear magnetic moments. In the absence of a magnetic field, the nuclear magnetic moments are randomly oriented, and the spin states are degenerate. When an external magnetic field is applied, the spin states have only 2 + 1 orientations available to them. A proton with = ½ has two available orientations. Similarly, for a quadrupolar nucleus with a nuclear spin value of one, the...

You might also read

Related Articles

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

Sort by
Same author

Preventing distal junctional kyphosis: Choosing a stable end for the lowest-instrumented vertebra is protective following adult cervical deformity surgery.

Journal of craniovertebral junction & spine·2026
Same author

Lipocalin-2-mediated oligodendrocyte pyroptosis contributes to post-stroke secondary white matter injury.

Brain research bulletin·2026
Same author

A novel score to predict successful endovascular recanalization of non-acute carotid artery occlusion.

Journal of neurointerventional surgery·2026
Same author

Flexible, super-resolution skin with in-sensor hyperdimensional computing for real-time pressure field perception.

Science advances·2026
Same author

Controlled release of rhBMP-2 from nanoparticle-loaded biomimetic graft promotes bone regeneration in a rat spinal fusion model.

Biomaterials advances·2026
Same author

A stacked multi-classifier for multi-modal data fusion in transcranial sonography-based Parkinson's disease assessment.

NPJ Parkinson's disease·2026
Same journal

Cation-templated synthesis of a Fe<sub>4</sub>Co<sub>20</sub> cyanometallate cluster.

Dalton transactions (Cambridge, England : 2003)·2026
Same journal

High-field multinuclear MAS NMR and synchrotron XANES reveal the influence of strontium salt chemistry on geopolymer nanostructure.

Dalton transactions (Cambridge, England : 2003)·2026
Same journal

Carbonyl insertion into metal-boron based clusters: pathway to a rhodathiacarborane.

Dalton transactions (Cambridge, England : 2003)·2026
Same journal

Simulation of displacement damage in CsPbBr<sub>3</sub> induced by neutron irradiation based on the Monte Carlo method.

Dalton transactions (Cambridge, England : 2003)·2026
Same journal

Photocatalysis-tribocatalysis synergy in oxygen vacancy-rich Zn<sub>2</sub>SnO<sub>4</sub>: mechanism and enhanced all-day performance.

Dalton transactions (Cambridge, England : 2003)·2026
Same journal

Two-dimensional Co/Ni coordination polymers: structure-activity relationship and bifunctional performance for electrocatalysis and energy storage.

Dalton transactions (Cambridge, England : 2003)·2026
See all related articles

Related Experiment Video

Updated: May 8, 2026

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains
07:42

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains

Published on: July 20, 2022

π-π stacking, spin density and magnetic coupling strength.

Yan-Hui Chi1, Jing-Min Shi, Hong-Nan Li

  • 1Department College of Chemistry, Chemical Engineering and Materials Science, Key Laboratory of Molecular and Nano Probes, Engineering Research Center of Pesticide and Medicine Intermediate Clean Production, Ministry of Education, Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals, Shandong Normal University, Jinan 250014, China. shijingmin1955@gmail.com.

Dalton Transactions (Cambridge, England : 2003)
|September 6, 2013
PubMed
Summary
This summary is machine-generated.

Spin density on atoms involved in pi-pi stacking significantly influences magnetic coupling strength in molecular systems. This study confirms spin density is a key factor, providing new insights into magnetic properties.

More Related Videos

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

Measuring the Spin-Lattice Relaxation Magnetic Field Dependence of Hyperpolarized [1-13C]pyruvate
11:57

Measuring the Spin-Lattice Relaxation Magnetic Field Dependence of Hyperpolarized [1-13C]pyruvate

Published on: September 13, 2019

Related Experiment Videos

Last Updated: May 8, 2026

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains
07:42

Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains

Published on: July 20, 2022

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

Measuring the Spin-Lattice Relaxation Magnetic Field Dependence of Hyperpolarized [1-13C]pyruvate
11:57

Measuring the Spin-Lattice Relaxation Magnetic Field Dependence of Hyperpolarized [1-13C]pyruvate

Published on: September 13, 2019

Area of Science:

  • Materials Science
  • Solid State Chemistry
  • Quantum Chemistry

Background:

  • Pi-pi stacking interactions are crucial intermolecular forces.
  • Their role in magnetic properties, particularly magnetic coupling strength, is an area of ongoing research.
  • The influence of spin density on this interaction remains experimentally and theoretically unconfirmed.

Purpose of the Study:

  • To investigate the relationship between spin density and magnetic coupling strength in pi-pi stacking systems.
  • To experimentally confirm the role of spin density in determining magnetic properties.
  • To establish guidelines for predicting magnetic coupling strength based on spin density and contact distance.

Main Methods:

  • Analysis of magnetostructural data from seven unpublished Cu(II) complexes.
  • Compilation and analysis of data from ten previously reported radical systems.
  • Correlation of spin density on short-contact atoms with observed magnetic coupling strengths.

Main Results:

  • Confirmed that spin density on short-contact atoms is a major factor in pi-pi stacking magnetic coupling strength.
  • Established thresholds for spin density and contact distance (e.g., C···C > 3.4 Å requires spin density > 0.1350 for significant coupling).
  • Observed that decreasing contact distance with temperature increases spin density, enhancing magnetic coupling.

Conclusions:

  • Spin density is a critical determinant of magnetic coupling strength in pi-pi stacking systems.
  • Specific spin density values and contact distances are necessary for achieving medium to strong magnetic coupling.
  • Low spin densities on short-contact atoms are identified as the primary reason for weak magnetic coupling in the studied complexes.