Video Experimental Relacionado
Updated: Jul 17, 2026
11:09
Constructing Thioether/Vinyl Sulfide-tethered Helical Peptides Via Photo-induced Thiol-ene/yne Hydrothiolation
Published on: August 1, 2018
U2Si9O23F4 (USH-8): un silicato de uranio de marco abierto con plantilla orgánica
Xiqu Wang1, Jin Huang, Allan J Jacobson
1Department of Chemistry, University of Houston, Houston, Texas 77204-5003, USA.
Journal of the American Chemical Society
|December 19, 2002
Resumen
Un nuevo marco de fluorosilicato de uranio, USH-8, fue sintetizado hidrotermalmente. Este material presenta capas dobles de silicato únicas y canales ocupados por cationes orgánicos, ofreciendo potencial para nuevas aplicaciones de materiales.
Área de la Ciencia:
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- Ciencia de los materiales Ciencia de los materiales.
- Ingeniería de Cristal Ingeniería de Cristal.
Sus antecedentes:
- Los materiales de marco abierto ofrecen propiedades sintonizables para diversas aplicaciones.
- Los compuestos a base de uranio son de interés debido a sus características electrónicas y estructurales únicas.
- Los fluorosilicatos representan una clase de compuestos inorgánicos con diversos motivos estructurales.
Objetivo del estudio:
- Para sintetizar y caracterizar un nuevo marco abierto de fluorosilicato de uranio.
- Investigar las características estructurales y el orden de clasificación dentro del marco.
- Explorar el potencial de tales materiales en áreas como el intercambio iónico o la catálisis.
Principales métodos:
- Síntesis hidrotermal utilizando hidróxido de tetrametilamonio y piridina-HF.
- Difracción de rayos X monocristalino para la determinación estructural.
- Análisis de la composición del marco y las estructuras de los canales.
Principales resultados:
- Se ha logrado la síntesis del fluorosilicato de uranio [CH3) 4N][C5H5NH]0.8CH3) 3NH) 0.2]U2Si9O23F4 (USH-8).
- El marco comprende dobles capas de silicato unidas por bipirámides pentagonales UO3F4.
- La estructura exhibe canales de 12 anillos a lo largo de [010] y canales de 7 anillos a lo largo de [100].
- Los cationes ordenados de tetrametilamonio (TMA) ocupan lados estrechos del canal, mientras que los cationes desordenados de piridinio y trimetilamonio ocupan secciones más amplias del canal.
Conclusiones:
- El nuevo compuesto USH-8 demuestra una compleja estructura de marco abierto con potencial para interacciones de moléculas invitadas.
- La distribución ordenada y desordenada de los cationes orgánicos dentro de los canales pone de relieve las funciones de dirección de la estructura.
- Esta síntesis amplía la biblioteca de materiales de marco abierto basados en uranio.
Videos de Conceptos Relacionados
02:00Molecular Models
Physical models representing molecular architectures of chemical compounds play essential roles in understanding chemistry. The use of molecular models makes it easier to visualize the structures and shapes of atoms and molecules.
03:02Organic Compounds
All living things are formed mostly of carbon compounds called organic compounds. The category of organic compounds includes both natural and synthetic compounds that contain carbon. Although a single, precise definition has yet to be identified by the chemistry community, most agree that a defining trait of organic molecules is the presence of carbon as the principal element, bonded to hydrogen and other carbon atoms. However, some carbon-containing compounds such as carbonates, cyanides, and...
01:16Nomenclature of Carboxylic Acid Derivatives: Acid Halides, Esters, and Acid Anhydrides
Naming Acid Halides
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
The IUPAC and common names of acid halides are derived from the corresponding carboxylic acids, by changing “ic acid” to “yl halide.” For example, as shown below, the IUPAC name ethanoyl chloride is derived from ethanoic acid, and the common name, acetyl chloride, is obtained from acetic acid.
01:28Structures of Carboxylic Acid Derivatives
Structure of Carboxylic Acid Derivatives
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
01:07Preparation of Acid Anhydrides
One of the methods for preparing symmetrical or unsymmetrical acid anhydrides involves the treatment of acid chlorides with the sodium salt of carboxylic acids. The reaction proceeds via a nucleophilic acyl substitution.
The carboxylate ion acts as a nucleophile that attacks the carbonyl carbon of the acid chloride to form a tetrahedral intermediate. Subsequently, the re-formation of the carbonyl group with the loss of the chloride ion as a leaving group leads to the formation of an acid...
The carboxylate ion acts as a nucleophile that attacks the carbonyl carbon of the acid chloride to form a tetrahedral intermediate. Subsequently, the re-formation of the carbonyl group with the loss of the chloride ion as a leaving group leads to the formation of an acid...
01:19Structure of Amines
The hybridized nitrogen atom in amines possesses a lone pair of electrons and is bound to three substituents with a bond angle of around 108°, which is less than the tetrahedral angle of 109.5°. However, the C–N–H bond angle is slightly larger at 112°, with a carbon–nitrogen bond length of 147 pm. This carbon–nitrogen bond length of of amines is longer than the carbon–oxygen bond of alcohols (143 pm) but shorter than alkanes’ carbon–carbon bond (154 pm). These aspects are illustrated in Figure...