Related Experiment Video
Updated: Jun 22, 2026
10:57
Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
Phase transitions in metal clusters and cluster catalysts.
1Department of Chemistry, University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, USA.
The Journal of Physical Chemistry. A
|June 23, 2009
Summary
Metal clusters exhibit unique phase transition properties, including numerous low-energy isomers and hysteresis, distinct from dielectric clusters. These characteristics influence their behavior and catalytic applications.
Area of Science:
- Physical Chemistry
- Materials Science
- Nanotechnology
Background:
- Phase transitions in metal and dielectric clusters reveal differences in energy, entropy, and coexistence bands.
- Metal clusters possess a notable abundance of low-excitation energy isomers compared to dielectric clusters.
Purpose of the Study:
- To compare the phase transition characteristics of metal clusters with those of dielectric clusters.
- To analyze hysteresis phenomena in large metal clusters during heating and cooling cycles.
- To explore the experimental and theoretical aspects of metal clusters as catalysts.
Main Methods:
- Comparative analysis of phase transition energies, entropy jumps, and coexistence band widths.
- Investigation of isomer populations and excitation energies in metal clusters.
- Analysis of hysteresis loops in cluster heating and cooling experiments.
Main Results:
- Metal clusters have lower phase transition energies but comparable entropy jumps and coexistence band widths to dielectric clusters.
- Metal clusters exhibit a higher density of low-lying isomers, partly due to electronic excited states.
- Hysteresis is observed in the phase transitions of large metal clusters.
Conclusions:
- Metal clusters display unique phase transition behaviors driven by their isomeric properties and electronic states.
- The observed hysteresis in metal clusters is a significant factor in their thermal behavior.
- Metal clusters show potential as catalysts, warranting further experimental and theoretical investigation.
![The Synthesis of [Sn10(Si(SiMe3)3)4]2- Using a Metastable Sn(I) Halide Solution Synthesized via a Co-condensation Technique](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F54498.jpg&w=3840&q=50)
Related Concept Videos
02:58Crystal 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...
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...
02:58Properties of Transition Metals
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.
02:32Bonding in Metals
Metallic bonds are formed between two metal atoms. A simplified model to describe metallic bonding has been developed by Paul Drüde called the “Electron Sea Model”.
02:42Valence 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...
03:02Colors 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.
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.
02:51Metal-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...
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...