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

¹H NMR: Interpreting Distorted and Overlapping Signals01:02

¹H NMR: Interpreting Distorted and Overlapping Signals

1.8K
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
1.8K
Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)01:20

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

2.0K
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...
2.0K
Valence Bond Theory02:42

Valence Bond Theory

11.8K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
11.8K
Atomic Nuclei: Nuclear Spin State Overview01:03

Atomic Nuclei: Nuclear Spin State Overview

2.3K
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...
2.3K
Atomic Nuclei: Nuclear Spin State Population Distribution01:14

Atomic Nuclei: Nuclear Spin State Population Distribution

2.6K
Near absolute zero temperatures, in the presence of a magnetic field, the majority of nuclei prefer the lower energy spin-up state to the higher energy spin-down state. As temperatures increase, the energy from thermal collisions distributes the spins more equally between the two states. The Boltzmann distribution equation gives the ratio of the number of spins predicted in the spin −½ (N−) and spin +½ (N+) states.
2.6K
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)01:22

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

1.7K
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...
1.7K

You might also read

Related Articles

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

Sort by
Same author

How visual attention underpins reading: Converging evidence from a meta-analysis of fMRI studies.

NeuroImage·2026
Same author

Artificial sparse neuron dendrites for visual information inference.

Science advances·2026
Same author

High encoding-sensitivity vision sensor with complementary nonlinear neuromorphic computing.

Nature communications·2026
Same author

Bacillus inoculation drives subtle taxonomic shifts in the bacterial communities of saline-alkaline wheat rhizosphere soil.

Environmental microbiome·2026
Same author

[Effectiveness analysis of using an orthopedic broken screw hollow saw in management of accidentally sutured surgical drains].

Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery·2026
Same author

Anion-regulated adsorption and solvation chemistry for high-voltage sodium-ion batteries.

Journal of colloid and interface science·2026

Related Experiment Video

Updated: Apr 12, 2026

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
11:44

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Published on: November 12, 2016

18.8K

Polymorphism-Dependent Spin-Crossover: Hysteretic Two-Step Spin Transition with an Ordered [HS-HS-LS] Intermediate

Jie Luan, Jian Zhou, Zhan Liu

  • 1‡Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, 510275 Guangzhou, P. R. China.

Inorganic Chemistry
|May 9, 2015
PubMed
Summary

A mononuclear iron(II) complex was studied in two forms. One form stays high-spin, while the other shows a two-step spin crossover with an intermediate phase.

More Related Videos

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
08:55

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Published on: June 7, 2018

9.1K
Practical Aspects of Sample Preparation and Setup of 1H R1ρ Relaxation Dispersion Experiments of RNA
08:17

Practical Aspects of Sample Preparation and Setup of 1H R1ρ Relaxation Dispersion Experiments of RNA

Published on: July 9, 2021

5.4K

Related Experiment Videos

Last Updated: Apr 12, 2026

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes
11:44

Spin Saturation Transfer Difference NMR SSTD NMR: A New Tool to Obtain Kinetic Parameters of Chemical Exchange Processes

Published on: November 12, 2016

18.8K
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
08:55

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses

Published on: June 7, 2018

9.1K
Practical Aspects of Sample Preparation and Setup of 1H R1ρ Relaxation Dispersion Experiments of RNA
08:17

Practical Aspects of Sample Preparation and Setup of 1H R1ρ Relaxation Dispersion Experiments of RNA

Published on: July 9, 2021

5.4K

Area of Science:

  • Solid-state chemistry
  • Materials science
  • Coordination chemistry

Background:

  • Spin crossover (SCO) complexes are molecular switches.
  • Understanding SCO mechanisms is crucial for materials design.

Purpose of the Study:

  • Investigate spin crossover behavior in a mononuclear iron(II) complex.
  • Characterize two distinct polymorphs of the complex.
  • Analyze the spin transition mechanism and intermediate phase.

Main Methods:

  • Polymorph isolation and characterization.
  • Temperature-dependent magnetic susceptibility measurements.
  • Structural analysis of polymorphs.

Main Results:

  • Two polymorphs (1a and 1b) of the iron(II) complex were isolated.
  • Polymorph 1b exhibited high-spin state across all temperatures.
  • Polymorph 1a displayed a two-step spin crossover with symmetry breaking and a 2:1 high-spin-low-spin intermediate phase.

Conclusions:

  • Polymorphism significantly influences spin crossover behavior.
  • The observed intermediate phase in polymorph 1a provides insights into cooperative spin transitions.
  • This study highlights the importance of structural control in designing functional spin crossover materials.