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: 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
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: 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
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
The Electrical Double Layer01:30

The Electrical Double Layer

222
In the region where two bulk phases meet, an intricate electric charge distribution arises due to charge transfer, ion adsorption, molecular orientation, and charge distortion. This complex distribution is commonly referred to as the electrical double layer.When a solid electrode interfaces with ions in an electrolyte solution, the speed of electron transfer dictates the rates of oxidation and reduction. The electrode acquires a charge through the escape of atoms into the solution as cations or...
222

You might also read

Related Articles

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

Sort by
Same author

DCSFormer: a high-precision method for cotton seedling point cloud organ segmentation.

Frontiers in plant science·2026
Same author

Automatic root measurement: a lightweight method for measuring pea root length.

Plant methods·2025
Same author

Electrically controlled interlayer trion fluid in electron-hole bilayers.

Science (New York, N.Y.)·2025
Same author

Robust High-Spin State in One-Dimensional CrX<sub>2</sub> (X = Cl, Br, I) at the Single-Chain Limit.

Journal of the American Chemical Society·2025
Same author

Optical imaging of flavor order in flat band graphene.

Nature communications·2025
Same author

Superconductivity and spin canting in spin-orbit-coupled trilayer graphene.

Nature·2025

Related Experiment Video

Updated: Apr 23, 2026

Fabricating van der Waals Heterostructures with Precise Rotational Alignment
09:25

Fabricating van der Waals Heterostructures with Precise Rotational Alignment

Published on: July 5, 2019

8.9K

Evolution of interlayer coupling in twisted molybdenum disulfide bilayers.

Kaihui Liu1, Liming Zhang2, Ting Cao3

  • 11] Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA [2] State Key Laboratory for Mesoscopic Physics, School of Physics and Collaborative Innovation Center of Quantum Matter, Peking University, Beijing 100871, China.

Nature Communications
|September 19, 2014
PubMed
Summary

Interlayer coupling in molybdenum disulfide bilayers significantly affects their indirect bandgap, with stacking configuration playing a key role. Steric effects influence interlayer separation and thus electronic properties.

More Related Videos

Residue-Free Fabrication of van der Waals Heterostructures of Two-Dimensional Materials
04:57

Residue-Free Fabrication of van der Waals Heterostructures of Two-Dimensional Materials

Published on: July 18, 2025

1.2K
Optimized Fabrication Procedure for High-Quality Graphene-based Moir&#233; Superlattice Devices
11:24

Optimized Fabrication Procedure for High-Quality Graphene-based Moiré Superlattice Devices

Published on: July 11, 2025

13.8K

Related Experiment Videos

Last Updated: Apr 23, 2026

Fabricating van der Waals Heterostructures with Precise Rotational Alignment
09:25

Fabricating van der Waals Heterostructures with Precise Rotational Alignment

Published on: July 5, 2019

8.9K
Residue-Free Fabrication of van der Waals Heterostructures of Two-Dimensional Materials
04:57

Residue-Free Fabrication of van der Waals Heterostructures of Two-Dimensional Materials

Published on: July 18, 2025

1.2K
Optimized Fabrication Procedure for High-Quality Graphene-based Moir&#233; Superlattice Devices
11:24

Optimized Fabrication Procedure for High-Quality Graphene-based Moiré Superlattice Devices

Published on: July 11, 2025

13.8K

Area of Science:

  • Condensed Matter Physics
  • Materials Science
  • Nanotechnology

Background:

  • Van der Waals coupling is a key method for engineering properties of 2D materials.
  • Previous studies on graphene and boron nitride showed phenomena like Fermi velocity renormalization.
  • Atomically thin transition metal dichalcogenides exhibit unique coupling behaviors.

Purpose of the Study:

  • To investigate the evolution of interlayer coupling in molybdenum disulfide (MoS2) bilayers based on twist angles.
  • To understand how stacking configuration influences the electronic properties of MoS2 bilayers.
  • To elucidate the underlying physical mechanisms governing interlayer coupling in MoS2.

Main Methods:

  • Experimental synthesis of as-grown molybdenum disulfide bilayers.
  • Measurement of indirect bandgap evolution with varying twist angles.
  • Ab initio calculations to model interlayer interactions and electronic structure.

Main Results:

  • The indirect bandgap size of MoS2 bilayers is highly dependent on stacking configuration.
  • A significant redshift in the bandgap was observed for AA- and AB-stacked bilayers.
  • Other twist angles showed a smaller, constant redshift, indicating distinct interlayer coupling.

Conclusions:

  • Interlayer coupling in MoS2 bilayers is strongly influenced by stacking configuration and twist angle.
  • Repulsive steric effects are identified as the primary cause for varying interlayer separations.
  • These variations in separation directly lead to the observed changes in bandgap energy.