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: 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

1.3K
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,...
1.3K
¹H NMR: Long-Range Coupling01:27

¹H NMR: Long-Range Coupling

2.5K
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...
2.5K
¹H NMR Chemical Shift Equivalence: Homotopic and Heterotopic Protons01:03

¹H NMR Chemical Shift Equivalence: Homotopic and Heterotopic Protons

3.9K
Protons in identical electronic environments within a molecule are chemically equivalent and have the same chemical shift. The replacement test is a useful tool to identify chemical equivalence and predict NMR spectra. A substituent replaces each of the protons being examined and the resulting molecules are compared. If the same molecule is obtained, the protons are equivalent or homotopic. Replacement of any hydrogens in ethane by chlorine yields chloroethane because all six protons are...
3.9K
2D NMR: Overview of Homonuclear Correlation Techniques01:16

2D NMR: Overview of Homonuclear Correlation Techniques

549
Homonuclear correlation spectroscopy (COSY) is a powerful technique used in Nuclear Magnetic Resonance (NMR) spectroscopy to study the correlations between nuclei of the same type within a molecule. It provides information about scalar couplings between adjacent nuclei, which helps determine connectivity and structural information. There are several COSY variants, each with its unique strengths and experimental parameters.
COSY90 is the standard two-dimensional (2D) COSY experiment that...
549
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)01:22

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

1.4K
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...
1.4K

You might also read

Related Articles

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

Sort by
Same author

A Computational Study of Reactions with Boric Acid Aimed to Promote the Utilization of Lignin.

Chemistry (Weinheim an der Bergstrasse, Germany)·2024
Same author

A Computational Study of the Promiscuity of the SAM-Dependent Methyltransferase AtHTMT1.

ACS omega·2022
Same author

Computational Study of the Degradation of S-Adenosyl Methionine in Water.

The journal of physical chemistry. A·2016
Same author

Solvent effects on the intramolecular conversion of trimethylsulfonium chloride to dimethyl sulfide and methyl chloride.

Physical chemistry chemical physics : PCCP·2014
Same author

A computational study of the activation of allenoates by Lewis bases and the reactivity of intermediate adducts.

Organic & biomolecular chemistry·2014
Same author

A computational study: reactivity difference between phosphine- and amine-catalyzed cycloadditions of allenoates and enones.

The Journal of organic chemistry·2014

Related Experiment Video

Updated: Dec 23, 2025

Synthesis of Nine-atom Deltahedral Zintl Ions of Germanium and their Functionalization with Organic Groups
08:15

Synthesis of Nine-atom Deltahedral Zintl Ions of Germanium and their Functionalization with Organic Groups

Published on: February 11, 2012

14.3K

Computational Evidence for Homonuclear GeIGeI Dative Bonds.

Timm Lankau1, Chin Hui Yu1

  • 1Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan.

The Journal of Physical Chemistry. A
|April 21, 2020
PubMed
Summary

Researchers discovered homonuclear dative bonds (HDBs) in germanium polycations. Geometric and electronic constraints force lone pairs into bonds, challenging traditional chemical bonding concepts.

More Related Videos

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
14:55

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy

Published on: September 17, 2017

15.9K
Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
09:37

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry

Published on: October 18, 2019

10.0K

Related Experiment Videos

Last Updated: Dec 23, 2025

Synthesis of Nine-atom Deltahedral Zintl Ions of Germanium and their Functionalization with Organic Groups
08:15

Synthesis of Nine-atom Deltahedral Zintl Ions of Germanium and their Functionalization with Organic Groups

Published on: February 11, 2012

14.3K
Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
14:55

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy

Published on: September 17, 2017

15.9K
Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
09:37

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry

Published on: October 18, 2019

10.0K

Area of Science:

  • Quantum Chemistry
  • Inorganic Chemistry
  • Materials Science

Background:

  • Traditional chemical bonding involves electron sharing or transfer between atoms.
  • Dative bonds typically occur between atoms of different electronegativity or oxidation states.
  • Geometric and electronic factors can influence bond formation in unusual ways.

Purpose of the Study:

  • To investigate the formation and nature of homonuclear dative bonds (HDBs) in germanium polycations.
  • To provide computational evidence for the existence of HDBs.
  • To challenge conventional understanding of chemical bonding.

Main Methods:

  • Density Functional Theory (DFT) calculations using the B3LYP/6-31+g(d,p) level of theory.
  • Atoms in Molecules (AIM) analysis to study electron density distribution.
  • Electron Localization Function (ELF) analysis to characterize bonding.

Main Results:

  • Confirmed the formation of HDBs between identical germanium atoms in polycations.
  • Demonstrated that electron density is unequally shared in HDBs.
  • Observed significant charge transfer, leading to formal charges that contradict standard chemical conventions.

Conclusions:

  • Homonuclear dative bonds are feasible under specific geometric and electronic constraints.
  • The concept of HDBs expands the understanding of chemical bonding.
  • Formal charges in HDBs may not accurately reflect electron distribution.