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

Colors and Magnetism03:02

Colors and Magnetism

Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
Valence Bond Theory02:42

Valence Bond Theory

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...
Crystal Field Theory - Octahedral Complexes02:58

Crystal Field Theory - Octahedral Complexes

Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Metal-Ligand Bonds02:51

Metal-Ligand Bonds

The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
Structural Isomerism02:34

Structural Isomerism

Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can be...
Electron Transport Chain: Complex III and IV01:43

Electron Transport Chain: Complex III and IV

During the electron transport chain, electrons from NADH and FADH2 are first transferred to complexes I and II, respectively. These two complexes then transfer the electrons to ubiquinol, which carries them further to complex III. Complex III passes the electrons across the intermembrane space to Cyt c, which carries them further to complex IV. Complex IV donates electrons to oxygen and reduces it to water. As electrons pass through complexes I, III, and IV, the energy released aids the pumping...

You might also read

Related Articles

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

Sort by
Same author

Excess of rare noncoding variants in several type 2 diabetes candidate genes among Asian Indian families.

Communications medicine·2025
Same author

Acceptorless oxidant-free dehydrogenation of amines catalyzed by Ru-hydride complexes of amide-acid/ester ligands.

Dalton transactions (Cambridge, England : 2003)·2025
Same author

Diagnosis and treatment of T/myeloid mixed phenotype acute leukaemia (T/M-MPAL).

EJHaem·2025
Same author

Lanthanide-Based Metal-Organic Frameworks Offering Hydrogen Bonding Cavities: Luminescent Characteristics and Sensing Applications.

Chemistry, an Asian journal·2025
Same author

Estimation of heart dose in left breast cancer radiotherapy: Assessment of vDIBH feasibility using the supervised machine learning algorithm.

Journal of applied clinical medical physics·2024
Same author

Challenges and opportunities in engineering next-generation 3D microelectronic devices: improved performance and higher integration density.

Nanoscale advances·2024

Related Experiment Video

Updated: May 8, 2026

Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging
07:41

Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging

Published on: July 19, 2016

Electron transfer from CdSe-ZnS core-shell quantum dots to cobalt(III) complexes.

Anuushka Pal1, Sumit Srivastava, Rajeev Gupta

  • 1Department of Chemistry, Indian Institute of Technology, Delhi-110016, India. sapra@chemistry.iitd.ac.in.

Physical Chemistry Chemical Physics : PCCP
|August 16, 2013
PubMed
Summary

Cobalt(III) complexes quench fluorescence in cadmium selenide-zinc sulfide quantum dots (QDs) primarily through static charge transfer. Electrochemical data confirm electron transfer as the main quenching mechanism, ruling out energy transfer.

More Related Videos

Synthesis and Performance Evaluations of ZnCoS/ZnCdS with Twin Crystal Structure for Multifunctional Redox Photocatalysis in Energy Applications
09:22

Synthesis and Performance Evaluations of ZnCoS/ZnCdS with Twin Crystal Structure for Multifunctional Redox Photocatalysis in Energy Applications

Published on: July 25, 2025

Compact Quantum Dots for Single-molecule Imaging
17:14

Compact Quantum Dots for Single-molecule Imaging

Published on: October 9, 2012

Related Experiment Videos

Last Updated: May 8, 2026

Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging
07:41

Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging

Published on: July 19, 2016

Synthesis and Performance Evaluations of ZnCoS/ZnCdS with Twin Crystal Structure for Multifunctional Redox Photocatalysis in Energy Applications
09:22

Synthesis and Performance Evaluations of ZnCoS/ZnCdS with Twin Crystal Structure for Multifunctional Redox Photocatalysis in Energy Applications

Published on: July 25, 2025

Compact Quantum Dots for Single-molecule Imaging
17:14

Compact Quantum Dots for Single-molecule Imaging

Published on: October 9, 2012

Area of Science:

  • Materials Science
  • Photochemistry
  • Nanotechnology

Background:

  • Core-shell quantum dots (QDs) like CdSe-ZnS offer tunable optical properties.
  • Cobalt(III) complexes are explored for their potential interactions with nanomaterials.
  • Understanding quenching mechanisms is crucial for QD applications.

Purpose of the Study:

  • To investigate the effect of cobalt(III) complexes with pyridyl anchors on CdSe-ZnS QD fluorescence.
  • To elucidate the primary mechanism responsible for fluorescence quenching.
  • To correlate quenching phenomena with electrochemical properties.

Main Methods:

  • Steady-state and time-resolved fluorescence spectroscopy.
  • Electrochemical analysis to determine energy level positions.
  • Synthesis and characterization of CdSe-ZnS QDs and cobalt(III) complexes.

Main Results:

  • Fluorescence quenching of CdSe-ZnS QDs was observed in the presence of cobalt(III) complexes.
  • Spectroscopic data indicated a predominantly static quenching component.
  • Electron transfer from QDs to Co(III) complexes was identified as the main quenching pathway.
  • Energy transfer mechanisms were systematically excluded.
  • Electrochemical data supported the electron transfer mechanism.

Conclusions:

  • The interaction between CdSe-ZnS QDs and cobalt(III) complexes leads to fluorescence quenching.
  • Charge transfer, specifically electron transfer, is the dominant mechanism.
  • The findings provide insights into QD-metal complex interactions for potential optoelectronic applications.