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

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: One-Bond Coupling01:17

Spin–Spin Coupling: One-Bond Coupling

1.2K
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,...
1.2K
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 involved orbitals. The...
1.3K
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)01:20

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

1.3K
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...
1.3K
NMR Spectroscopy: Spin–Spin Coupling01:08

NMR Spectroscopy: Spin–Spin Coupling

2.6K
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...
2.6K
Atomic Nuclei: Nuclear Spin State Overview01:03

Atomic Nuclei: Nuclear Spin State Overview

1.5K
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...
1.5K

You might also read

Related Articles

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

Sort by
Same author

Anti-topological crystal and non-Abelian liquid in twisted semiconductor bilayers.

Nature communications·2026
Same author

Observation of Braid-Protected Unpaired Exceptional Points.

Physical review letters·2026
Same author

Ionizable guanidine-based lipid nanoparticle for targeted mRNA delivery and cancer immunotherapy.

Science advances·2025
Same author

Research on the flow properties of fracturing fluids through nozzles during the flowback process in oil wells.

Scientific reports·2025
Same author

The Framingham steatosis index as a predictor of advanced CKM syndrome in US adults: Evidence from NHANES 2001 to 2018.

Medicine·2025
Same author

Peripheral blood mesenchymal stem cells repair oxidative damage and apoptosis in an H<sub>2</sub>O<sub>2</sub>-induced vitiligo oxidative stress in vitro model via the IL-10-mediated PI3K/AKT pathway.

European journal of medical research·2025

Related Experiment Video

Updated: Nov 15, 2025

Molecular Entanglement and Electrospinnability of Biopolymers
07:59

Molecular Entanglement and Electrospinnability of Biopolymers

Published on: September 3, 2014

14.9K

Exceptional Spin Liquids from Couplings to the Environment.

Kang Yang1, Siddhardh C Morampudi2, Emil J Bergholtz1

  • 1Department of Physics, Stockholm University, AlbaNova University Center, 106 91 Stockholm, Sweden.

Physical Review Letters
|March 5, 2021
PubMed
Summary

Researchers discovered a new type of spin liquid in open systems, featuring emergent exceptional points. This novel phase is stable and has experimental implications due to environmental coupling.

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

10.2K
High-Temperature and High-Pressure In situ Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy
08:55

High-Temperature and High-Pressure In situ Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy

Published on: October 9, 2020

5.8K

Related Experiment Videos

Last Updated: Nov 15, 2025

Molecular Entanglement and Electrospinnability of Biopolymers
07:59

Molecular Entanglement and Electrospinnability of Biopolymers

Published on: September 3, 2014

14.9K
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

10.2K
High-Temperature and High-Pressure In situ Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy
08:55

High-Temperature and High-Pressure In situ Magic Angle Spinning Nuclear Magnetic Resonance Spectroscopy

Published on: October 9, 2020

5.8K

Area of Science:

  • Condensed Matter Physics
  • Quantum Many-Body Systems

Background:

  • The Kitaev honeycomb model describes a gapless spin liquid phase requiring time-reversal symmetry.
  • Open quantum systems are crucial for understanding real-world phenomena due to environmental interactions.

Purpose of the Study:

  • To investigate the emergence of new quantum phases in open systems.
  • To explore the effects of environmental coupling on spin liquid properties.

Main Methods:

  • Analysis of an open Kitaev honeycomb model with generic environmental coupling.
  • Identification of emergent exceptional points and Fermi arcs.

Main Results:

  • A new spin liquid phase with emergent exceptional points is established.
  • This phase is robust against perturbations, unlike the original gapless phase.
  • The non-Hermitian skin effect leads to sensitivity to boundary conditions.

Conclusions:

  • Open systems can host novel spin liquid phases with unique properties.
  • Emergent exceptional points and stability are key features of these new phases.
  • Environmental coupling is a crucial factor in realizing exotic quantum states.