Video Experimental Relacionado
Updated: May 13, 2026
08:12
Surface Functionalization of Metal-Organic Frameworks for Improved Moisture Resistance
Published on: September 5, 2018
H3O2 ligando puente en un marco metálico-orgánico. Conocimiento del equilibrio aqua-hidroxohidroxilo: un estudio
Richard F D'Vries1, Victor A de la Peña-O'Shea, Natalia Snejko
1Department of New Architectures in Materials Chemistry, Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, c/Sor Juana Inés de la Cruz, 3, 28049 Madrid, Spain.
Journal of the American Chemical Society
|March 21, 2013
Resumen
Este estudio investiga el equilibrio entre el agua-hidroxo (O2H3) y el hidroxilo (OH) en las estructuras metal-orgánicas de escandio (Sc-MOF). La investigación identifica la fase termodinámicamente estable (O2H3) Sc-MOF y sus aplicaciones catalíticas.
Área de la Ciencia:
- Química de los materiales Química de los materiales
- Química supramolecular de las moléculas.
- La catálisis de la catálisis.
Sus antecedentes:
- Las estructuras metálicas orgánicas (MOF) son materiales versátiles con propiedades sintonizables.
- Comprender la especiación de los ligandos dentro de los MOF es crucial para controlar su estabilidad y función.
- Las especies de agua-hidroxo (O2H3) y hidroxilo (OH) juegan un papel en la síntesis hidrotermal y la estabilidad de los MOF basados en escandio (Sc-MOF).
Objetivo del estudio:
- Para investigar el equilibrio entre el agua-hidroxo (O2H3) y las especies de hidroxilo (OH) en Sc-MOFs.
- Para determinar la estabilidad relativa y las condiciones de formación de diferentes fases de Sc-MOF.
- Explorar la estructura electrónica y la actividad catalítica del sintetizado Sc-MOF.
Principales métodos:
- Síntesis experimental y caracterización de Sc-MOFs bajo diferentes condiciones hidrotermales y pH.
- Estudios computacionales (teoría funcional de densidad) para calcular las energías relativas de diferentes especies.
- Análisis de la estructura electrónica y ensayos catalíticos heterogéneos en la cianosilación de aldehídos.
Principales resultados:
- Se aisló con éxito la fase termodinámicamente estable [Sc3{3,5-DSB}2{μ-O2H}3{μ-OH}2{H2O}2] ((O2H3{Sc-MOF}).
- La fase hidroxilo-dominante [Sc3{3,5-DSB}2{μ-OH}3{H2O}4] fue identificada como un precursor, no aislable como una fase pura.
- Se informaron dos compuestos Sc-MOF adicionales, que aparecen en diferentes rangos de pH, para el análisis comparativo.
Conclusiones:
- El estudio aclara el equilibrio dependiente del pH entre las especies aqua-hidroxo e hidroxilo en Sc-MOFs.
- La fase (O2H3) Sc-MOF exhibe una estabilidad termodinámica superior bajo condiciones hidrotermales específicas.
- El (O2H3) Sc-MOF sintetizado demuestra potencial en catálisis heterogénea para reacciones de cianosilación.
Más Videos Relacionados
07:20Discovery and Synthesis Optimization of Isoreticular Al(III) Phosphonate-Based Metal-Organic Framework Compounds Using High-Throughput Methods
Published on: October 6, 2023
04:51Synthesis of Triazole and Tetrazole-Functionalized Zr-Based Metal-Organic Frameworks Through Post-Synthetic Ligand Exchange
Published on: June 23, 2023
Videos de Conceptos Relacionados
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...
00:56Extraction: Advanced Methods
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is formed in...
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...
01:23Complexation Equilibria: Overview
Complexation reactions take place when dative or coordinate covalent bonds form between metal ions and ligands. The compounds formed in these reactions are called coordination compounds. The number of bonds formed between the metal ion and the ligands is called its coordination number. Generally, most metal ions in an aqueous solution are solvated by water molecules and thus exist as aqua complexes.
The equilibrium constant of the complexation reaction is represented as the formation constant...
The equilibrium constant of the complexation reaction is represented as the formation constant...
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...
01:19Complexation Equilibria: The Chelate Effect
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...