Video Experimental Relacionado
Updated: Jul 20, 2026
10:51
The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Pentaciano-hierro (II) como grupo donante de electrones para la óptica no lineal: propiedades de respuesta media y
Benjamin J Coe1, Josephine L Harries, Madeleine Helliwell
1School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, UK. b.coe@man.ac.uk
Journal of the American Chemical Society
|September 14, 2006
Resumen
Este estudio detalla sales de hierro complejas con propiedades ópticas no lineales (NLO) sintonizables. Los cambios en el solvente y el pH alteran significativamente sus respuestas NLO, ofreciendo potencial para materiales ópticos conmutables.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- Ciencia de los materiales Ciencia de los materiales.
- La fotoquímica es la fotoquímica.
Sus antecedentes:
- Los centros de cianuro de hierro rico en electrones ((II) coordinados con los ligandos piridil con sustituyentes que aceptan electrones forman sales complejas.
- Estos materiales exhiben bandas de transferencia de carga de metal a ligando (MLCT) en el espectro visible.
Objetivo del estudio:
- Caracterizar sales complejas y determinar sus respuestas ópticas no lineales (NLO) cuadráticas moleculares.
- Investigar la influencia del disolvente y el pH en las propiedades de NLO y las transiciones MLCT.
- Compare las propiedades de NLO de los complejos de hierro (II) con los análogos relacionados de rutenio (II).
Principales métodos:
- La espectroscopia de absorción electrónica es una espectroscopia de absorción electrónica.
- Voltametría cíclica La voltametría cíclica es la voltametría cíclica.
- La dispersión de Hyper-Rayleigh (HRS) es un fenómeno
- La espectroscopia de Stark (electroabsorción) también se utiliza.
- Teoría funcional de densidad dependiente del tiempo (TD-DFT) y cálculos de campo finito.
Principales resultados:
- Se sintetizaron y caracterizaron las sales complejas con centros {Fe{II}{CN}{5}{3}{4}}} y sustituyentes de piridinio.
- Se observó un solvatocromismo significativo, con un aumento de las respuestas NLO de las soluciones acuosas a las de metanol.
- La acidificación de las soluciones acuosas cambió de forma reversible las propiedades lineales y NLO.
- Los cálculos mostraron una buena concordancia con los datos experimentales, lo que confirma la disminución de la respuesta de NLO a la protonación.
- Los complejos de hierro (II) exhibieron un solvatocromismo más fuerte, lo que condujo a respuestas NLO superiores en el metanol en comparación con los análogos de rutenio (II).
Conclusiones:
- Los complejos de hierro sintetizado (II) muestran propiedades sintonizables de NLO influenciadas por el disolvente y el pH.
- Estos hallazgos ponen de relieve el potencial para el desarrollo de materiales ópticos conmutables basados en complejos metal-orgánicos.
- Los efectos de los disolventes juegan un papel crucial en la modulación del rendimiento NLO de estos sistemas.
Videos de Conceptos Relacionados
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...
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...
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.
02:34Structural 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...
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...
01:11ortho–para-Directing Activators: –CH3, –OH, –NH2, –OCH3
All ortho–para directors, excluding halogens, are activating groups. These groups donate electrons to the ring, making the ring carbons electron-rich. Consequently, the reactivity of the aromatic ring towards electrophilic substitution increases. For instance, the nitration of anisole is about 10,000 times faster than the nitration of benzene. The electron-donating effect of the methoxy group in anisole activates the ortho and para positions on the ring and stabilizes the corresponding...
01:18Aromatic Hydrocarbon Cations: Structural Overview
Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group with both...
Removing one hydrogen from the intervening CH2 group with both...