Related Experiment Video
Updated: Oct 10, 2025
08:57
A Novel Technique for Generating and Observing Chemiluminescence in a Biological Setting
Published on: March 9, 2017
8.6K
Luminescent chromium(0) and manganese(I) complexes
Christina Wegeberg1, Oliver S Wenger1
1Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland. oliver.wenger@unibas.ch.
Dalton Transactions (Cambridge, England : 2003)
|December 15, 2021
Summary
Newly discovered chromium(0) and manganese(I) complexes exhibit metal-to-ligand charge transfer (MLCT) emission. These 3d6 emitters show potential for developing novel luminescent first-row transition metal complexes.
Area of Science:
- Inorganic Chemistry
- Photochemistry
- Materials Science
Background:
- First-row transition metal complexes, particularly 3d6 systems, are of interest for luminescence applications.
- Ruthenium(II) polypyridines are well-established luminescent materials, but their precious metal nature limits widespread use.
- Developing earth-abundant alternatives is crucial for sustainable and cost-effective technologies.
Purpose of the Study:
- To highlight recently discovered chromium(0) and manganese(I) complexes.
- To investigate their emission properties originating from metal-to-ligand charge transfer (MLCT) excited states.
- To explore strategies for enhancing luminescence in 3d6 complexes.
Main Methods:
- Synthesis of novel chromium(0) and manganese(I) complexes utilizing chelating isocyanide ligands.
- Characterization of photophysical properties, including MLCT lifetimes and luminescence quantum yields.
- Analysis of emission mechanisms and deactivation pathways.
Main Results:
- Access to a new class of 3d6 emitters based on chromium(0) and manganese(I).
- Observed MLCT lifetimes in the nanosecond regime in solution at room temperature.
- Achieved luminescence quantum yields are currently low but show promise.
- Photophysical properties are comparable to established ruthenium(II) polypyridines.
Conclusions:
- Chelating isocyanide ligands are effective in creating luminescent 3d6 complexes.
- Insights gained into counteracting nonradiative MLCT deactivation pathways.
- Findings are relevant for developing future luminescent complexes of iron(II) and cobalt(III).
- Potential for earth-abundant alternatives to precious metal-based emitters.
Related Concept Videos
03:02Colors and Magnetism
12.5K
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...
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...
12.5K
02:58Properties of Transition Metals
27.7K
Transition metals are defined as those elements that have partially filled d orbitals. As shown in Figure 1, the d-block elements in groups 3–12 are transition elements. The f-block elements, also called inner transition metals (the lanthanides and actinides), also meet this criterion because the d orbital is partially occupied before the f orbitals.
27.7K
02:58Crystal Field Theory - Octahedral Complexes
28.2K
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...
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...
28.2K
02:42Valence Bond Theory
9.8K
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...
9.8K
03:45Formation of Complex Ions
24.2K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
24.2K
01:19Complexation Equilibria: The Chelate Effect
723
In complexation reactions, metal atoms or cations interact with ligands to form donor-acceptor adducts called metal complexes. Ligands that bind through one donor site are monodentate, ligands with two donor sites are bidentate, and those with more than two donor sites are polydentate ligands. For example, ethylene diamine is a bidentate ligand that binds through two nitrogen donor atoms, forming a five-membered ring. EDTA is a polydentate ligand that binds through four oxygen and two nitrogen...
723