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

Diamagnetic Shielding of Nuclei: Local Diamagnetic Current01:14

Diamagnetic Shielding of Nuclei: Local Diamagnetic Current

1.6K
An applied magnetic field causes the electrons present in the molecule to circulate, setting up a local diamagnetic current within the molecule. The local diamagnetic current arising from circulating sigma-bonding electrons induces a magnetic field, Blocal that opposes the applied magnetic field, B0. The effective magnetic field experienced by these nuclei is given by the difference between the applied and local magnetic fields in a phenomenon called local diamagnetic shielding. Essentially,...
1.6K
Atomic Nuclei: Nuclear Magnetic Moment00:59

Atomic Nuclei: Nuclear Magnetic Moment

3.6K
All atomic nuclei are positively charged. When they have a nonzero spin, they behave like rotating charges. As a consequence of their charge and spin, these nuclei generate a magnetic field (B). This, in turn, gives rise to a magnetic moment (μ), which is randomly oriented in the absence of an external magnetic field. When an external magnetic field (B0) is applied, the magnetic moment vectors can align with the field or against it in 2 + 1 orientations. A hydrogen nucleus, which is just a...
3.6K
Atomic Nuclei: Magnetic Resonance01:05

Atomic Nuclei: Magnetic Resonance

1.4K
The number of nuclear spins aligned in the lower energy state is slightly greater than those in the higher energy state. In the presence of an external magnetic field, as the spins precess at the Larmor frequency, the excess population results in a net magnetization oriented along the z axis. When a pulse or a short burst of radio waves at the Larmor frequency is applied along the x axis, the coupling of frequencies causes resonance and flips the nuclear spins of the excess population from the...
1.4K
Atomic Nuclei: Nuclear Spin State Overview01:03

Atomic Nuclei: Nuclear Spin State Overview

2.2K
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...
2.2K
Nuclear Stability03:18

Nuclear Stability

24.2K
Protons and neutrons, collectively called nucleons, are packed together tightly in a nucleus. With a radius of about 10−15 meters, a nucleus is quite small compared to the radius of the entire atom, which is about 10−10 meters. Nuclei are extremely dense compared to bulk matter, averaging 1.8 × 1014 grams per cubic centimeter. If the earth’s density were equal to the average nuclear density, the earth’s radius would be only about 200 meters.
To hold positively charged protons together...
24.2K
Nuclear Binding Energy02:13

Nuclear Binding Energy

15.2K
The difference between the calculated and experimentally measured masses is known as the mass defect of the atom. In the case of helium-4, the mass defect indicates a “loss” in mass of 4.0331 amu – 4.0026 amu = 0.0305 amu. The loss in mass accompanying the formation of an atom from protons, neutrons, and electrons is due to the conversion of that mass into energy that is evolved as the atom forms. The nuclear binding energy is the energy produced when the atoms’ nucleons are bound...
15.2K

You might also read

Related Articles

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

Sort by
Same author

Correction to "Chemical Bonding and Aromaticity in Furan, Pyrrole, and Thiophene: A Magnetic Shielding Study".

The Journal of organic chemistry·2024
Same author

Sulfinfinitenes: infinitenes of fused thiophene rings.

Chemical communications (Cambridge, England)·2024
Same author

Excited-state aromaticity reversals in norcorrole.

Physical chemistry chemical physics : PCCP·2024
Same author

Aromaticity and Antiaromaticity Reversals between the Electronic Ground State and the Two Lowest Triplet States of Thiophene.

Chemphyschem : a European journal of chemical physics and physical chemistry·2024
Same author

Aromaticity in the Electronic Ground and Lowest Triplet States of Molecules with Fused Thiophene Rings.

Chemistry (Weinheim an der Bergstrasse, Germany)·2023
Same author

α-Functionalisation of Cyclic Sulfides Enabled by Lithiation Trapping.

Angewandte Chemie (International ed. in English)·2023

Related Experiment Video

Updated: Mar 27, 2026

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

6.2K

Exploring Chemical Bonds through Variations in Magnetic Shielding.

Peter B Karadakov1, Kate E Horner1

  • 1Department of Chemistry, University of York , Heslington, York YO10 5DD, United Kingdom.

Journal of Chemical Theory and Computation
|January 7, 2016
PubMed
Summary

Quantum chemistry calculations reveal molecular magnetic shielding variations, offering a detailed view of chemical bonding beyond electron density. This provides new insights into molecular structure and interactions.

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

16.2K
Paramagnetic Relaxation Enhancement for Detecting and Characterizing Self-Associations of Intrinsically Disordered Proteins
07:24

Paramagnetic Relaxation Enhancement for Detecting and Characterizing Self-Associations of Intrinsically Disordered Proteins

Published on: September 23, 2021

2.4K

Related Experiment Videos

Last Updated: Mar 27, 2026

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

6.2K
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

16.2K
Paramagnetic Relaxation Enhancement for Detecting and Characterizing Self-Associations of Intrinsically Disordered Proteins
07:24

Paramagnetic Relaxation Enhancement for Detecting and Characterizing Self-Associations of Intrinsically Disordered Proteins

Published on: September 23, 2021

2.4K

Area of Science:

  • Quantum chemistry
  • Computational chemistry
  • Spectroscopy

Background:

  • Nuclear magnetic shieldings determine chemical shifts in NMR experiments.
  • Traditional NMR techniques measure shieldings only at nuclei.
  • Quantum chemical methods offer advanced capabilities for calculating magnetic properties.

Purpose of the Study:

  • To explore the spatial distribution of isotropic magnetic shieldings around molecules.
  • To demonstrate the utility of magnetic shielding isosurfaces and contour plots for visualizing chemical bonding.
  • To compare the detail provided by magnetic shielding analysis with traditional electron density descriptions.

Main Methods:

  • Utilizing quantum chemical methods to calculate isotropic magnetic shieldings.
  • Analyzing magnetic shielding variations in space around small organic molecules (butadiene, ethane, ethene, ethyne).
  • Representing magnetic shielding data using isosurfaces and contour plots.

Main Results:

  • Isotropic magnetic shielding variations around molecules provide a clear picture of chemical bonding.
  • This method reveals details of chemical bonding superior to total electron density analysis.
  • Spatial mapping of magnetic shieldings offers a novel perspective on molecular electronic structure.

Conclusions:

  • Quantum chemical calculation of magnetic shieldings in 3D space is a powerful tool.
  • Magnetic shielding isosurfaces offer a more detailed and intuitive representation of chemical bonding.
  • This approach enhances our understanding of molecular electronic structure and chemical interactions.