Jove
Visualize
Contáctanos
JoVE
x logofacebook logolinkedin logoyoutube logo
ACERCA DE JoVE
Visión GeneralLiderazgoBlogCentro de Ayuda JoVE
AUTORES
Proceso de PublicaciónConsejo EditorialAlcance y PolíticasRevisión por ParesPreguntas FrecuentesEnviar
BIBLIOTECARIOS
TestimoniosSuscripcionesAccesoRecursosConsejo Asesor de BibliotecasPreguntas Frecuentes
INVESTIGACIÓN
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchivo
EDUCACIÓN
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualCentro de Recursos para ProfesoresSitio de Profesores
Términos y Condiciones de Uso
Política de Privacidad
Políticas

Videos de Conceptos Relacionados

Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)01:20

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

1.1K
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...
1.1K
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)01:22

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

1.1K
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...
1.1K
Spin–Spin Coupling Constant: Overview01:08

Spin–Spin Coupling Constant: Overview

959
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...
959
¹H NMR: Long-Range Coupling01:27

¹H NMR: Long-Range Coupling

1.8K
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...
1.8K
Spin–Spin Coupling: One-Bond Coupling01:17

Spin–Spin Coupling: One-Bond Coupling

1.0K
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,...
1.0K
NMR Spectroscopy: Spin–Spin Coupling01:08

NMR Spectroscopy: Spin–Spin Coupling

1.5K
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...
1.5K

También podría leer

Artículos Relacionados

Artículos vinculados a este trabajo por autores compartidos, revista y gráfico de citas.

Ordenar por
Same author

On-Water Surface Synthesis of 2D Conjugated Metal-Organic Framework Films With Controllable Layer Orientation Enabling High-Performance Chemiresistive Sensing.

Advanced materials (Deerfield Beach, Fla.)·2026
Same author

Ultranarrow nanochannels in a staggered two-dimensional polymer membrane enhance electric double-layer coverage for osmotic energy harvesting.

Nature communications·2026
Same author

Defects That Magnetize Beyond Monolayer PtSe<sub>2</sub>.

Small (Weinheim an der Bergstrasse, Germany)·2026
Same author

Strain-Field-Induced Bandgap Opening in Bilayer Graphene.

Small (Weinheim an der Bergstrasse, Germany)·2026
Same author

Metal-Free Ferromagnetism in Triangulene Two-Dimensional Frameworks.

Journal of the American Chemical Society·2026
Same author

Prediction of strong Cu(I)-He interaction at open metal sites enables isotope-selective helium adsorption.

Nature communications·2026

Video Experimental Relacionado

Updated: Jul 18, 2025

Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers
08:28

Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers

Published on: September 19, 2017

8.0K

Control de acoplamiento magnético en dímeros triangulares

Hongde Yu1, Thomas Heine1,2,3

  • 1Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Bergstraße 66c, 01062 Dresden, Germany.

Journal of the American Chemical Society
|August 23, 2023
PubMed
Resumen

Los investigadores exploraron el magnetismo libre de metales utilizando dímeros triangulares. Lograron un fuerte acoplamiento antiferromagnético y realizaron un acoplamiento ferromagnético en dímeros dopados con nitrógeno, allanando el camino para nuevos dispositivos espintrónicos.

Más Videos Relacionados

Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
09:06

Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope

Published on: March 24, 2019

8.1K
Magnetic Tweezers for the Measurement of Twist and Torque
11:41

Magnetic Tweezers for the Measurement of Twist and Torque

Published on: May 19, 2014

23.3K

Videos de Experimentos Relacionados

Last Updated: Jul 18, 2025

Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers
08:28

Single-molecule Manipulation of G-quadruplexes by Magnetic Tweezers

Published on: September 19, 2017

8.0K
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
09:06

Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope

Published on: March 24, 2019

8.1K
Magnetic Tweezers for the Measurement of Twist and Torque
11:41

Magnetic Tweezers for the Measurement of Twist and Torque

Published on: May 19, 2014

23.3K

Área de la Ciencia:

  • Ciencias de los materiales
  • Química Cuántica
  • Física de la materia condensada

Sus antecedentes:

  • El magnetismo libre de metales es crucial para nuevos dispositivos electrónicos.
  • Los triángulos son monómeros orgánicos prometedores para la espintrónica debido a la polarización de espín inherente.
  • Las limitaciones actuales incluyen un acoplamiento magnético débil y la falta de aplicaciones a temperatura ambiente.

Objetivo del estudio:

  • Investigar el acoplamiento magnético en dímeros triangulares.
  • Mejorar las interacciones magnéticas para aplicaciones espintrónicas prácticas.
  • Explorar estrategias para controlar la fuerza y el signo de acoplamiento magnético.

Principales métodos:

  • Los cálculos de los primeros principios en 24 dímeros triangulares.
  • Análisis de la estructura electrónica y las interacciones magnéticas.
  • Ajuste de las configuraciones moleculares (planar, retorcido) y dopaje (nitrógeno).

Principales resultados:

  • Se logra un fuerte acoplamiento antiferromagnético (hasta -144 meV, -198 meV en configuraciones planas).
  • Correlación establecida entre la brecha de banda, el acoplamiento electrónico y la interacción antiferromagnética.
  • Realizó acoplamiento ferromagnético en dímeros triangulares dopados con nitrógeno, desafiando la regla Ovchinnikov.

Conclusiones:

  • Acoplamiento magnético sintonizable demostrado en dímeros triangulares a través de la modificación estructural.
  • Proporcionó información a nivel molecular para mejorar las interacciones magnéticas.
  • Se han abierto nuevas vías para el diseño de ferromagnetos sin metal para la espintrónica.