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: One-Bond Coupling01:17

Spin–Spin Coupling: One-Bond Coupling

1.5K
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,...
1.5K
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)01:20

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

1.7K
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...
1.7K
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)01:22

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

1.5K
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...
1.5K
NMR Spectroscopy: Spin–Spin Coupling01:08

NMR Spectroscopy: Spin–Spin Coupling

3.2K
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...
3.2K
Spin–Spin Coupling Constant: Overview01:08

Spin–Spin Coupling Constant: Overview

1.5K
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...
1.5K
Electron Orbital Model01:18

Electron Orbital Model

72.3K
Orbitals are the areas outside of the atomic nucleus where electrons are most likely to reside. They are characterized by different energy levels, shapes, and three-dimensional orientations. The location of electrons is described most generally by a shell or principal energy level, then by a subshell within each shell, and finally, by individual orbitals found within the subshells.
The first shell is closest to the nucleus, and it has only one subshell with a single spherical orbital called the...
72.3K

You might also read

Related Articles

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

Sort by
Same author

Genomic Predictors of Perineural Invasion in Cutaneous Squamous Cell Carcinoma: Insights from an MD Anderson Cohort.

Journal of the American Academy of Dermatology·2026
Same author

How to approach the deep inferior epigastric perforator flap revision for optimal aesthetics.

Gland surgery·2026
Same author

Coexistence of weak and strong coupling in a photonic molecule through dissipative coupling to a quantum dot.

Nanophotonics (Berlin, Germany)·2025
Same author

Unlocking multiphoton emission from a single-photon source through mean-field engineering.

Science advances·2025
Same author

Frey Syndrome After Mohs Micrographic Surgery for Squamous Cell Carcinoma In Situ.

Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.]·2025
Same author

The gut microbiome enhances breast cancer immunotherapy following bariatric surgery.

JCI insight·2025

Related Experiment Video

Updated: Feb 6, 2026

Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry
08:23

Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry

Published on: March 9, 2018

9.3K

Negative-Mass Effects in Spin-Orbit Coupled Bose-Einstein Condensates.

David Colas1, Fabrice P Laussy2,3, Matthew J Davis1

  • 1ARC Centre of Excellence in Future Low-Energy Electronics Technologies, School of Mathematics and Physics, University of Queensland, St Lucia, Queensland 4072, Australia.

Physical Review Letters
|August 18, 2018
PubMed
Summary

Negative effective mass in quantum systems can halt expansion and create density fringes. This study reveals self-interference of wave packets as the cause, leading to novel counterpropagating packets in spin-orbit coupled Bose-Einstein condensates.

More Related Videos

A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer SMPS-ICPMS
11:18

A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer SMPS-ICPMS

Published on: July 11, 2017

11.2K
Quantitative Metabolomics of Saccharomyces Cerevisiae Using Liquid Chromatography Coupled with Tandem Mass Spectrometry
07:25

Quantitative Metabolomics of Saccharomyces Cerevisiae Using Liquid Chromatography Coupled with Tandem Mass Spectrometry

Published on: January 5, 2021

5.0K

Related Experiment Videos

Last Updated: Feb 6, 2026

Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry
08:23

Real-time Breath Analysis by Using Secondary Nanoelectrospray Ionization Coupled to High Resolution Mass Spectrometry

Published on: March 9, 2018

9.3K
A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer SMPS-ICPMS
11:18

A Practical Guide on Coupling a Scanning Mobility Sizer and Inductively Coupled Plasma Mass Spectrometer SMPS-ICPMS

Published on: July 11, 2017

11.2K
Quantitative Metabolomics of Saccharomyces Cerevisiae Using Liquid Chromatography Coupled with Tandem Mass Spectrometry
07:25

Quantitative Metabolomics of Saccharomyces Cerevisiae Using Liquid Chromatography Coupled with Tandem Mass Spectrometry

Published on: January 5, 2021

5.0K

Area of Science:

  • Quantum physics
  • Condensed matter physics

Background:

  • Negative effective masses can be engineered in quantum systems.
  • Recent experiments show negative effective mass can halt Bose-Einstein condensate expansion, causing density fringes.

Purpose of the Study:

  • To explain the cause of density fringes observed in spin-orbit coupled Bose-Einstein condensates with negative effective mass.
  • To investigate novel phenomena arising from negative mass parameters in quantum systems.

Main Methods:

  • Theoretical analysis of wave packet dynamics in systems with engineered dispersion relations.
  • Examination of spin-orbit coupled Bose-Einstein condensates.

Main Results:

  • The observed density fringes are caused by the self-interference of wave packets when one mass parameter is negative.
  • Spin-orbit coupled Bose-Einstein condensates can exhibit regimes with two negative mass parameters.
  • This leads to the emergence of counterpropagating self-interfering packets.

Conclusions:

  • Self-interference of wave packets is the fundamental mechanism behind density fringes in negative effective mass systems.
  • The study identifies a new regime in spin-orbit coupled Bose-Einstein condensates with potential for novel quantum phenomena.