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)

1.1K
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

1.0K
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...
1.0K
¹H NMR: Long-Range Coupling01:27

¹H NMR: Long-Range Coupling

2.0K
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...
2.0K
Radicals: Electronic Structure and Geometry01:07

Radicals: Electronic Structure and Geometry

4.2K
This lesson delves into the geometry of a radical, which is influenced by the electronic structure of the molecule. The principle is similar to that of a lone pair, where the unpaired electron influences the geometry at the radical center.
Accordingly, the structure of a trivalent radical lies between the geometries of carbocations and carbanions. An sp2-hybridized carbocation is trigonal planar, while an sp3-hybridized carbanion is trigonal pyramidal. Here, the difference in geometry is...
4.2K
Electron Paramagnetic Resonance (EPR) Spectroscopy: Organic Radicals01:17

Electron Paramagnetic Resonance (EPR) Spectroscopy: Organic Radicals

2.7K
Ideally, an unpaired electron shows a single peak in the EPR spectrum due to the transition between the two spin energy states. However, coupling interactions can occur between the spins of the unpaired electron and any neighboring spin-active nuclei. This hyperfine coupling results in hyperfine splitting, where the EPR signal is split into multiplets. The signals split into 2nI + 1 peaks, where n is the number of equivalent nuclei and I is the nuclear spin. These splitting patterns provide...
2.7K
Radical Reactivity: Overview01:11

Radical Reactivity: Overview

2.2K
Radicals, the highly reactive species, gain stability by undergoing three different reactions. The first reaction involves a radical-radical coupling, in which a radical combines with another radical, forming a spin‐paired molecule. The second reaction is between a radical and a spin‐paired molecule, generating a new radical and a new spin‐paired molecule. The third reaction is radical decomposition in a unimolecular reaction, forming a new radical and a spin‐paired...
2.2K

You might also read

Related Articles

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

Sort by
Same author

Photo-Ionization Spectrum of 1,2-Azaborine: A Theoretical Study.

Chemphyschem : a European journal of chemical physics and physical chemistry·2026
Same author

The Jahn-Teller and pseudo-Jahn-Teller effects in hexafluorobenzene radical cation: nonradiative decay and radiative emission.

Physical chemistry chemical physics : PCCP·2026
Same author

Full-dimensional investigation of the photoionization spectrum of benzonitrile.

The Journal of chemical physics·2026
Same author

State-to-state dynamics of H + LiHe+ (v = 0, j = 0) → LiH+ + He reaction.

The Journal of chemical physics·2025
Same author

Influence of molecular orientation on photovoltaic performance in double donor with fullerene and non-fullerene acceptor-based heterojunctions.

Physical chemistry chemical physics : PCCP·2025
Same author

Control of optically dark nσ* state mediated photodissociation of thioanisole.

The Journal of chemical physics·2025

Related Experiment Video

Updated: Sep 11, 2025

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
08:22

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization

Published on: August 6, 2018

7.0K

Vibronic Coupling in Formamide Radical Cation: A Full Dimensional Quantum Mechanical Study.

Yarram Ajay Kumar1, Mamilwar Rani1, Susanta Mahapatra1

  • 1School of Chemistry, University of Hyderabad, Hyderabad, India.

Journal of Computational Chemistry
|August 14, 2025
PubMed
Summary

This study investigates formamide's role in prebiotic chemistry using advanced quantum calculations. It analyzes vibronic spectra and internal conversion dynamics, providing insights into molecular behavior relevant to early life formation.

More Related Videos

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
08:54

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid

Published on: January 25, 2020

5.7K
Measurements of Long-range Electronic Correlations During Femtosecond Diffraction Experiments Performed on Nanocrystals of Buckminsterfullerene
08:44

Measurements of Long-range Electronic Correlations During Femtosecond Diffraction Experiments Performed on Nanocrystals of Buckminsterfullerene

Published on: August 22, 2017

7.8K

Related Experiment Videos

Last Updated: Sep 11, 2025

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
08:22

Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization

Published on: August 6, 2018

7.0K
Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid
08:54

Vibrational Spectra of a N719-Chromophore/Titania Interface from Empirical-Potential Molecular-Dynamics Simulation, Solvated by a Room Temperature Ionic Liquid

Published on: January 25, 2020

5.7K
Measurements of Long-range Electronic Correlations During Femtosecond Diffraction Experiments Performed on Nanocrystals of Buckminsterfullerene
08:44

Measurements of Long-range Electronic Correlations During Femtosecond Diffraction Experiments Performed on Nanocrystals of Buckminsterfullerene

Published on: August 22, 2017

7.8K

Area of Science:

  • Physical Chemistry
  • Quantum Chemistry
  • Astrochemistry

Background:

  • Formamide is a simple molecule crucial for prebiotic chemistry.
  • Understanding its electronic and vibrational properties is key to studying early life formation.

Purpose of the Study:

  • To perform extensive ab initio calculations on formamide's electronic states.
  • To construct and analyze a vibronic coupling Hamiltonian.
  • To investigate nuclear dynamics and internal conversion processes.

Main Methods:

  • Ab initio calculations for electronic states.
  • Construction of a 4x4 vibronic coupling Hamiltonian in a diabatic basis.
  • Quantum dynamical methods for nuclear dynamics (time-independent and time-dependent).
  • Taylor expansion of electronic Hamiltonian elements.

Main Results:

  • A detailed vibronic Hamiltonian was developed and employed.
  • Computed vibronic spectra were assigned and compared with experimental data.
  • Internal conversion population dynamics were studied to understand nonadiabatic couplings.

Conclusions:

  • The study provides a theoretical framework for formamide's vibronic structure.
  • Insights into nonadiabatic effects on nuclear dynamics were gained.
  • This research contributes to understanding formamide's reactivity in prebiotic environments.